Problems with water in your basement can often be corrected by controlling water above ground, according to a North Dakota State University engineer. “Correcting those above-ground problems may prevent structural damage to your home as well as dry up those basement damp spots,” says Ken Hellevang, an agricultural engineer with the North Dakota State University Extension Service. He notes that saturated soil increases the soil pressure on the basement wall which can lead to cracks, shifts, collapses and other structural problems. Start first by looking to the roof, Hellevang advises. An inch of water on 1,000 square feet of roof amounts to about 623 gallons of water. A foot of compacted snow on that same roof could contain up to 4 inches of water, or nearly 2,500 gallons. “Getting all that water away from the house is a big first step to preventing basement problems,” Hellevang says. “That’s why all eavetrough downspouts should have extensions to carry the water several feet from the house.” Just as the roof is sloped to shed water, the ground around your home should be sloped too, he notes. A slope of about 1 inch per foot near the wall is usually adequate, Hellevang says. Also, the ground should be sloped to carry the water away from the downspout discharge. “In some cases it is desirable to place an impermeable material under the soil next to the wall to ensure that the water flows away from the house,” he says. In addition to good drainage above ground, a drainage system below ground is important to keeping your home dry, Hellevang says. A properly installed drainage system at the house foundation and under the basement floor will ensure a dry basement and eliminate saturated soil conditions next to the wall. A study of leakage problems showed that more than 90 percent were due to improperly installed drainage systems. The engineer says a properly installed foundation drainage system includes drainpipes placed alongside the footing. In areas with high water tables, a drainage system can also be installed around the inside of the footing and under the basement floor. Using granular material to allow the movement of water and filtering material to keep soil from plugging drain pipes is essential to keeping the system functioning for the life of the house Hellevang says. Granular backfill should be used next to basement walls, he notes. Using soils that don’t drain well can cause pressure on the walls if the soils become saturated. Poor- draining soils also increase the potential for moisture or water vapor to move through the wall into the basement. In certain areas, that moisture can carry minerals that are detrimental to the concrete. Window wells also need to be correctly constructed with drains linked to the foundation drains. Soil elevation in the window well should be several inches below bottom of window and sloped to the drain. “The cost of installing the drainage system during new construction is minimal and the benefits are priceless,” Hellevang says. “Because so many problems can result from a poorly designed or installed drainage system, it’s important to install the system correctly or find a contractor who knows how to do the job. “In existing houses with wet basements, correcting the problem may be as easy as controlling the water above the ground,” Hellevang says. “If that’s not successful, then an exterior and interior drainage system may need to be installed.”

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Sequence for painting a room is from top to bottom: Ceiling first, then walls, then windows, doors and finally baseboards. Great interior painting is as easy as one-two-three There are many reasons why interior painting is the nation’s most popular home improvement project. Painting can quickly and dramatically transform the appearance of a room, an apartment or an entire home; it’s personally rewarding; it’s inexpensive; and it’s fun. Moreover, interior painting is easy. According to the Rohm and Haas Paint Quality Institute, even novices can often get professional painting results by following just three simple rules Rule number one: Prepare the surface properly Good paint performance depends on good paint adhesion, and paint adheres best to surfaces that are clean and sound. Before picking up a brush or roller, it’s important to make sure the surface is “inviting” to the paint. Accumulated dirt, dust and grime should be removed from walls, ceilings and trim with a detergent-water solution. After washing, the surfaces should be thoroughly rinsed with water and allowed to dry completely. Next, a putty knife should be used to fill cracks, holes and other surface imperfections with either spackling compound or a quality acrylic caulk. If spackling is used, after it is dry it should be sanded smooth and flush with the surface; caulk should be smoothed and feathered as it is applied. Finally, if walls or ceilings have water stains or other serious discol-oration, then before painting, it may be necessary to coat them with a latex or oil-based stain-blocking primer to prevent the stains from bleeding through the new paint. Rule number two: Use only top quality paint Compared with ordinary interior paints, top quality finishes are much easier to work with and offer superior long-term performance. In terms of application benefits, top quality paints won’t spatter or tend to show brush marks. And since they hide better than ordinary paints, a single coat is often sufficient to give a great looking paint job and save on time, labor and cost. Top quality interior paints also are tougher and more durable than ordinary interior paints, according to experts at the Paint Quality Institute. They resist fading, yellowing and staining. And even if they do get spotted or stained, discoloration can often be washed off without damaging the finish. Rule number three: Invest in quality tools To get the most from top quality interior paint, it should be applied with high quality brushes and rollers. Not only will they apply the paint more evenly, but they will also make the job more effortless The best brushes tend to be well balanced, hold a lot of paint and apply the paint evenly. Look for brushes with tightly packed bristles and test them for springiness. And be sure they don’t fan too much. When applying the more popular latex or water-based interior paints, it’s important to use brushes and rollers with synthetic bristles and covers. They’ll maintain the proper stiffness and keep their shape regardless of the amount of water they’re exposed to. Most oil-based or alkyd paints can be applied with brushes and rollers made either of synthetic or natural materials. Remember. interior painting can be as simple as one-two-three. But there are no shortcuts. Good surface preparation, top quality paint and high quality tools are all essential to get the best Ceilings First cut in a 2 inch wide strip with a brush around the edges of the ceiling. Switch to a roller (usually 3/8 or 1/2 inch for flat paints) with a 4 – 5 ft extension pole.. Staring at a corner, paint a section about 3 feet square. Use a zigzag pattern, paint a W” pattern on the ceiling, which will disperse the paint on the roller evenly. Fill in this 3 ft section without reloading the roller until you have complete coverage of this section. Continue to cover the ceiling, working across its shortest dimension in 3 foot square sections, overlapping while paint is wet to minimize lap marks. Walls Starting at the ceiling, cut in 2 inch strip with a brush. Continue with the brush to cut in 2 inch strips in corners, around windows, doors, cabinets and baseboards. Note – there are tools available at your paint retail outlets that help make this “edging” job easier. Other “tricks” include sliding the roller cover off the holder slightly so the rollers edge gets closer to ceiling, window or door. Switch to a roller and paint in a vertical direction using a zigzag pattern. Push the roller upward on the first stroke, then form an “M” pattern to evenly distribute the paint on the roller. (working in 3 ft sections is recommended). Fill in the “M” pattern without reloading the roller until you have complete coverage of the area. Continue with this approach until the wall is finished. Touching up spots you missed when the paint is wet will help minimize sheen potential sheen differences. Most manufacturers recommend that when you finish one wall, make sure you have enough paint to complete the next entire wall. Starting with another can of paint in the middle of a wall can result in slightly different colors, which will be perceptible side by side, but not wall to wall. Doors Open door wide to reach all parts to be covered. Protect hinges and other metal with masking tape. Always start at the top. If the door is paneled, paint the panels first, the horizontal sections next and finally the vertical sections. If the door opens into the room you are painting, use the same color on the latch edge that you have used for the rest of the door. If it opens into the next room, do not paint the hinged edge. It should be the same color as the other room Decks Due to the growing popularity of decks, there are now a wide variety of Deck finishes – ranging from conventional penetrating ones to new water based latex ones. In the alkyd category, there are clears, semi transparent and opaque finishes. In latex, semi transparent and opaque. Many homeowners are starting to use the semi transparent or opaque to maximize the protection and duration of their deck coating. Begin by cleaning and power washing to remove dirt, mildew and old coatings. If you are using a clear, penetrating coatings, deck brightening products help restore a “new wood” look to the wood.. Both sides of the railings should also be powerwashed. Brushes and Rollers – Once the deck is clean and thoroughly dry, start with a brush on the outside of the deck, on tops of the railing and work your way down to the deck, then in toward the house. Then switch to a roller for the deck, starting at an outside edge and working toward the house. Use even pressure on the roller on each board to give uniform coverage and sheen. Spraying is another way to coat decks – faster than brush/roller, but you must be sure to protect scrubs etc. from overspray. Spray equipment can be rented at many paint stores, home centers or rental companies. Check with a paint professional for tip size and pressure setting – which will depend on the type of coating you use. Spray railings first, unless the railings are to be a different color than the deck. Then the deck should be coated first. One trip for protecting plants or other objects from overspray is to tape kraft paper to the outside of the railing, which will catch the overspray. When spraying the deck itself, spray evenly over a six foot square area, then go over that area with a 1/2 inch nap roller to spread coating evenly into deck. Continue this procedure in sections until deck is covered. Be sure to use a large shield (such as 4 ft square piece of cardboard) when painting alongside the house to protect it from overspray. Windows Of all the woodwork in the home, windows suffer the most stress. Constant exposure to temperature changes and condensation means that windows often need to be painted more frequently than doors, moldings and trim. Unfortunately, the process involved in painting windows can be confusing. To simplify things, the Rohm and Haas Paint Quality Institute offers some window painting guidelines that can save you time, money and aggravation. Start by gathering the right tools for window painting: a 1 1/2″ or 2″ quality brush (use synthetic bristles if you are painting with one of the popular latex interior paints); a cutting-in brush for precision work; a paint shield or masking tape; a screwdriver; enough top quality paint to complete the job. Remove locks, curtain hooks and other hardware from the windows. This will speed your work and produce a better-looking paint job. Double-hung windows For double-hung windows, follow this six-step procedure: 1. Raise the bottom sash and lower the top sash most of the way, so that there is a 6″ overlap. Paint the bottom horizontal section of the top sash, then the accessible vertical members. Use care to keep paint from getting in between sash and frame which can “glue” the window in place. 2. Nearly close the upper and lower sashes, then finish painting the rest of the top sash. 3. Paint the entire bottom sash. 4. After allowing the sashes to dry, paint the window frame. 5. Close the windows and paint the exposed parts of the runners. If your windows have sash cords, avoid getting paint on them. 6. Paint the window sill and apron. Casement windows If your home has any casement windows (windows that open out or in, rather than up or down), use a different technique: 1. Open the windows and paint the top, side and bottom edges. 2. Paint the crossbars and frame casings. 3. Complete the job by painting the sill and apron. Regardless of the type of windows you are painting, if you have a steady hand, you can keep paint on the frame and off the glass by using the cutting-in brush. But be sure to overlap the paint onto the glass slightly to help seal off moisture and drafts. There are two other techniques for keeping paint off of the window panes: holding up a paint shield as you work or applying masking tape to the glass. When using tape, press it firmly to the glass to keep excess paint from creeping beneath it. (If stray specks of paint get onto the glass, simply remove them with a razor blade.) Remove the tape before the paint dries to a hard film. Some final tips from the experts at the Paint Quality Institute: Before starting to paint, repair any damage to the window and properly prepare the surface. This can be done by scraping off old paint, then sanding, and priming any spots where bare wood shows. (Get more advice on surface preparation at your local paint retailer, hardware store or decorating center.) Paint windows early in the day so that they have enough time to dry before you close them in the evening. Finish painting each piece in the direction of the wood grain.

Brought to you by Napoleon Home Inspections

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Moisture in your home can be a problem when there is either too much or too little. Humidity is the amount of moisture or water vapour in the air. People tend to feel more comfortable when the relative humidity is between 35-50%. High levels of humidity can cause problems, such as a room to feel stuffy and for biological contaminants to thrive. High levels of moisture can also affect your home by causing wood to rot and condensation on windows. Removing moisture can make a room feel more comfortable. Moisture can enter the home in many ways. Outside sources include the soil, surface water and outside air. Breathing and perspiration by you and your family are a major source of moisture. So is showering, bathing, drying clothers, washing dishes and cooking. Most homes have more than one source of moisture. A little prevention can keep excess moisture out of your home. Identify moisture sources in your home and try to correct them. Symptoms of humidity problems Too much humidity 1. Condensation on windows 2. Wet stains on walls and ceilings 3. Moldy bathroom 4. Musty smells 5. Allergic reactions 6. Can lead to damage to the house and contends 7. Ongoing allergies 8. Promotes mold growth and dust mite proliferation Too Little Humidity 1. Chapped skin and lips 2. Scratchy nose and throat 3. Static and sparks 4. Problems with electronic equipment 5. Damage to furniture In addition to identifying and correcting any of your homes moisture sources, a dehumidifier can be used to help control the humidity in your home. General Types of Humidifiers 1. Heat pump dehumidifier Draws moist air over coils that are close to freezing allowing the moisture to condense and be drained away. 2. Chemical absorbent dehumidifier Absorbs moisture from the air with a desiccant, a drying agent, located on a heat exchange wheel. This type was designed for use in hot, humid climates. 3. Dehumidifying ventilator Sensor-controlled exhaust fan. You set the control to the desired humidity level. These are particularly effective if yor humidity source is your basement. Suggestions for use and care of home dehumidifiers 1. Empty the tank; wipe all surfaces dry to reduce the growth of microogaanisms. Be sure you unplug the unit from the electrical socket first. 2. Follow manufactures instructions on the use of cleaning products or disinfectants. 3. Do not dehumidify to indoor relative humidity levels below 35%. Lower humidity levels may cause chapped lips and skin, scratchy nose and throat, breathing problems, and static problems. Hygrometers, available for purchase at most hardware stores, may be used to measure humidity levels. 4. Clean the dehumidifier, as directed, at the end of the hot-humid season or when you know it will not be used frequently. Before storage, make sure all parts are dry and dispose of all used demineralization. 5. Check operational temperatures before purchasing dehumidifiers, as some are designed for temperatures above 75 degrees F, and some will function at temperatures down to 45 degree F. 6. Stop using your dehumidifier and contact your physician if you have respiratory problems.

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Landscaping: Landscape Plan Landscaping is a lot of work and can cost a lot of money. For these reasons, most do-it-yourselfers go with a 3 to 5 year landscape plan. That way the work and cost can be spread out over a few years.A good plan is essential in landscaping. Without it, you’ll end up wasting a lot of time and money. At this point, you should know what style your landscape will be and what function it will perform for you.You also should have a good idea of what plants you want to incorporate in your plan.As a homeowner, look at where you spend most of your time and really focus on first enhancing the views from there. To keep the costs down, you can also try to re-use some of the plants in your existing landscape. Getting Started If you go with an independent designer, the plan could cost you up to a couple hundred dollars. But many nurseries will provide you with a free plan if you’re buying their plants.You can draw up your own landscape plan since the basic principles of landscape design are not that complex. But there are a lot of things to consider so you might want to have a landscape pro look over your plan before you start on it. You’ll need graph paper to draw out your plan. We use the kind with the grids laid out in eighth-inch scale. You’ll need to measure out the size of your lot, plus the dimensions of your house. You’ll also need a pretty good idea of where the house sits in the yard in relation to the boundaries of the property. To be exact, measure from one corner of the house to a couple landmarks like a corner of the yard or a gate. TIP: We’ve learned to use tracing paper over our basic yard drawing at this point so you don’t have to re-draw it over and over again. Drawing Your Own Plan Here are examples of how we drew up an informal and formal plan. Informal Plan We framed the front of the house with taller plants anchoring the corners with a shade tree on one side and an ornamental tree on the other. Spreading these out a couple feet will make a small house seem a bit bigger. Next, we put in a series of medium-sized shrubs along the foundation to cover any exposed block. The entry was framed on each side with a group of taller deciduous shrubs. We used a series of short shrubs to round off the outside edges. Then we filled the area in with a mass planting of perennials. The finished plan shows how carefully planned the informal layout really is, despite the random look it presents. Formal Plan We started with a low, formal hedge, trimmed in this case to a height of two feet. We’d want straight lines and square corners for the hedge, nothing rounded or curved. Next, we framed the entry with a pair of upright, conical evergreens. Along the foundation, we continued the geometric sequence with a globe-shaped, medium-sized shrub. For color, we filled in the middle of the beds with tall perennials that would be visible above the hedge. To finish, we anchored the corners of the house with a pair of ornamental trees, pruned to hold their shape.If there was an immediate need for a privacy barrier with the neighbours yard, we could put up an 8-foot privacy fence along the boundary. An alternative would be a hedge of tall shrubs–like lilacs or arborvitae, but that would definitely take longer. A tall hedge like that would also be a way to soften a long featureless wall on one side of the house.A row of evergreens on the north side of the house would provide a real nice wind barrier in the winter.And a few shade trees on the south side would eventually shade the house in the summer but drop their leaves in the winter and let the sun warm the house.

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Lawn care is a very important aspect of home maintenance. Lawns need to be regularly mowed, weeded, edged, controlled for pests, and fertilized to ensure a beautiful compliment to your home. Often the amount of time needed to properly care for a lawn can be extensive. With todays busy schedules, people often dont have the time to care for their yard properly. Using a lawn care service is an inexpensive way to keep the yard looking nice without taking up all your free time. There are several types of lawn care services from large professional organizations to the neighbourhood kid making a few extra dollars. Who to choose will depend on the size of your lawn and what type of maintenance youll need. For weekly or bi weekly lawn trimmings, it is quite acceptable to choose someone at a budget price. If you are looking for more intense upkeep, look for a company that has a lot of experience in professional landscape maintenance. Most people who opt for using a neighbour to do their regular lawn upkeep will not ask for a service contract. For this type of work, it is not necessary and even if they dont show up, you can get another person or a professional service in without too much hassle. Make sure though, that you pay after the work is completed so you can inspect the job and ensure quality work. You may need to occasionally hire a professional to do some more sophisticated things like pest control or landscaping. If hiring a professional lawn service company, there are several things you should look for. Ensure they have experience in and the ability to do full service lawn care. This would include mowing, weeding, edging and fertilizing. They may also provide services such as pest control, seeding and landscape design. Choose only the services you will need on a regular basis and obtain quotes for additional items as necessary. Most services will give you a maintenance contract that will outline the days they will come, how often they will provide service, and what services are included. These are generally done on a monthly basis for a set fee. Find out how to cancel your service and what steps need to be taken to ensure you are able to easily change if needed. Ask for and get proof of insurance. In case the company damages your lawn, you want to be sure you are covered. Check how long they have been in business, and if they have referrals check them.

Gray Rollins is a featured writer for LawnCareNut.com

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Masonry–brick, stone, terra-cotta, and concrete block–is found on nearly every historic building. Structures with all-masonry exteriors come to mind immediately, but most other buildings at least have masonry foundations or chimneys. Although generally considered “permanent,” masonry is subject to deterioration, especially at the mortar joints. Repointing, also known simply as “pointing”or–somewhat inaccurately–”tuck pointing”*, is the process of removing deteriorated mortar from the joints of a masonry wall and replacing it with new mortar. Properly done, repointing restores the visual and physical integrity of the masonry. Improperly done, repointing not only detracts from the appearance of the building, but may also cause physical damage to the masonry units themselves. The purpose of this Brief is to provide general guidance on appropriate materials and methods for repointing historic masonry buildings and it is intended to benefit building owners, architects, and contractors. The Brief should serve as a guide to prepare specifications for repointing historic masonry buildings. It should also help develop sensitivity to the particular needs of historic masonry, and to assist historic building owners in working cooperatively with architects, architectural conservators and historic preservation consultants, and contractors. Although specifically intended for historic buildings, the guidance is appropriate for other masonry buildings as well. This publication updates Preservation Briefs 2: Repointing Mortar Joints in Historic Brick Buildings to include all types of historic unit masonry. The scope of the earlier Brief has also been expanded to acknowledge that the many buildings constructed in the first half of the 20th century are now historic and eligible for listing in the National Register of Historic Places, and that they may have been originally constructed with portland cement mortar. *Tuckpointing technically describes a primarily decorative application of a raised mortar joint or lime putty joint on top of flush mortar joints. Historical Background Mortar consisting primarily of lime and sand has been used as an integral part of masonry structures for thousands of years. Up until about the mid-19th century, lime or quicklime (sometimes called lump lime) was delivered to construction sites, where it had to be slaked, or combined with water. Mixing with water caused it to boil and resulted in a wet lime putty that was left to mature in a pit or wooden box for several weeks, up to a year. Traditional mortar was made from lime putty, or slaked lime, combined with local sand, generally in a ratio of 1 part lime putty to 3 parts sand by volume. Often other ingredients, such as crushed marine shells (another source of lime), brick dust, clay, natural cements, pigments, and even animal hair were also added to mortar, but the basic formulation for lime putty and sand mortar remained unchanged for centuries until the advent of portland cement or its forerunner, Roman cement, a natural, hydraulic cement. Portland cement was patented in Great Britain in 1824. It was named after the stone from Portland in Dorset which it resembled when hard. This is a fast-curing, hydraulic cement which hardens under water. Portland cement was first manufactured in the United States in 1872, although it was imported before this date. But it was not in common use throughout the country until the early 20th century. Up until the turn of the century portland cement was considered primarily an additive, or “minor ingredient” to help accelerate mortar set time. By the 1930s, however, most masons used a mix of equal parts portland cement and lime putty. Thus, the mortar found in masonry structures built between 1873 and 1930 can range from pure lime and sand mixes to a wide variety of lime, portland cement, and sand combinations. In the 1930s more new mortar products intended to hasten and simplify masons’ work were introduced in the U.S. These included masonry cement, a premixed, bagged mortar which is a combination of portland cement and ground limestone, and hydrated lime, machine-slaked lime that eliminated the necessity of slaking quicklime into putty at the site. Identifying the Problem Before Repointing The decision to repoint is most often related to some obvious sign of deterioration, such as disintegrating mortar, cracks in mortar joints, loose bricks or stones, damp walls, or damaged plasterwork. It is, however, erroneous to assume that repointing alone will solve deficiencies that result from other problems. The root cause of the deterioration–leaking roofs or gutters, differential settlement of the building, capillary action causing rising damp, or extreme weather exposure–should always be dealt with prior to beginning work. Without appropriate repairs to eliminate the source of the problem, mortar deterioration will continue and any repointing will have been a waste of time and money. Use of Consultants. Because there are so many possible causes for deterioration in historic buildings, it may be desirable to retain a consultant, such as a historic architect or architectural conservator, to analyze the building. In addition to determining the most appropriate solutions to the problems, a consultant can prepare specifications which reflect the particular requirements of each job and can provide oversight of the work in progress. Referrals to preservation consultants frequently can be obtained from State Historic Preservation Offices, the American Institute for Conservation of Historic and Artistic Works (AIC), the Association for Preservation Technology (APT), and local chapters of the American Institute of Architects (AIA). Finding an Appropriate Mortar Match Preliminary research is necessary to ensure that the proposed repointing work is both physically and visually appropriate to the building. Analysis of unweathered portions of the historic mortar to which the new mortar will be matched can suggest appropriate mixes for the repointing mortar so that it will not damage the building because it is excessively strong or vapor impermeable. Examination and analysis of the masonry units–brick, stone or terra cotta–and the techniques used in the original construction will assist in maintaining the building’s historic appearance. A simple, non- technical, evaluation of the masonry units and mortar can provide information concerning the relative strength and permeability of each–critical factors in selecting the repointing mortar–while a visual analysis of the historic mortar can provide the information necessary for developing the new mortar mix and application techniques. Although not crucial to a successful repointing project, for projects involving properties of special historic significance, a mortar analysis by a qualified laboratory can be useful by providing information on the original ingredients. However, there are limitations with such an analysis, and replacement mortar specifications should not be based solely on laboratory analysis. Analysis requires interpretation, and there are important factors which affect the condition and performance of the mortar that cannot be established through laboratory analysis. These may include: the original water content, rate of curing, weather conditions during original construction, the method of mixing and placing the mortar, and the cleanliness and condition of the sand. The most useful information that can come out of laboratory analysis is the identification of sand by gradation and color. This allows the color and the texture of the mortar to be matched with some accuracy because sand is the largest ingredient by volume. In creating a repointing mortar that is compatible with the masonry units, the objective is to achieve one that matches the historic mortar as closely as possible, so that the new material can coexist with the old in a sympathetic, supportive and, if necessary, sacrificial capacity. The exact physical and chemical properties of the historic mortar are not of major significance as long as the new mortar conforms to the following criteria: # The new mortar must match the historic mortar in color, texture and tooling. (If a laboratory analysis is undertaken, it may be possible to match the binder components and their proportions with the historic mortar, if those materials are available.) # The sand must match the sand in the historic mortar. (The color and texture of the new mortar will usually fall into place if the sand is matched successfully.) # The new mortar must have greater vapor permeability and be softer (measured in compressive strength) than the masonry units. # The new mortar must be as vapor permeable and as soft or softer (measured in compressive strength) than the historic mortar. (Softness or hardness is not necessarily an indication of permeability; old, hard lime mortars can still retain high permeability.) Mortar Analysis Methods for analyzing mortars can be divided into two broad categories: wet chemical and instrumental. Many laboratories that analyze historic mortars use a simple wet-chemical method called acid digestion, whereby a sample of the mortar is crushed and then mixed with a dilute acid. The acid dissolves all the carbonate-containing minerals not only in the binder, but also in the aggregate (such as oyster shells, coral sands, or other carbonate-based materials), as well as any other acid-soluble materials. The sand and fine-grained acid-insoluble material is left behind. There are several variations on the simple acid digestion test. One involves collecting the carbon dioxide gas given off as the carbonate is digested by the acid; based on the gas volume the carbnate content of the mortar can be accurately determined (Jedrzejewska, 1960). Simple acid digestion methods are rapid, inexpensive, and easy to perform, but the information they provide about the original composition of a mortar is limited to the color and texture of the sand. The gas collection method provides more information about the binder than a simple acid digestion test. Instrumental analysis methods that have been used to evaluate mortars include polarized light or thin-section microscopy, scanning electron microscopy, atomic absorption spectroscopy, X-ray diffraction, and differential thermal analysis. All instrumental methods require not only expensive, specialized equipment, but also highly-trained experienced analysts. However, instrumental methods can provide much more information about a mortar. Thin-section microscopy is probably the most commonly used instrumental method. Examination of thin slices of a mortar in transmitted light is often used to supplement acid digestion methods, particularly to look for carbonate-based aggregate. For example, the new ASTM test method, ASTM C 1324-96 “Test Method for Examination and Analysis of Hardened Mortars” which was designed specifically for the analysis of modern lime-cement and masonry cement mortars, combines a complex series of wet chemical analyses with thin-section microscopy. The drawback of most mortar analysis methods is that mortar samples of known composition have not been analyzed in order to evaluate the method. Historic mortars were not prepared to narrowly defined specifications from materials of uniform quality; they contain a wide array of locally derived materials combined at the discretion of the mason. While a particular method might be able to accurately determine the original proportions of a lime-cement-sand mortar prepared from modern materials, the usefulness of that method for evaluating historic mortars is questionable unless it has been tested against mortars prepared from materials more commonly used in the past. Lorraine Schnabel. Properties of Mortar Mortars for repointing should be softer or more permeable than the masonry units and no harder or more impermeable than the historic mortar to prevent damage to the masonry units. It is a common error to assume that hardness or high strength is a measure of appropriateness, particularly for lime-based historic mortars. Stresses within a wall caused by expansion, contraction, moisture migration, or settlement must be accommodated in some manner; in a masonry wall, these stresses should be relieved by the mortar rather than by the masonry units. A mortar that is stronger in compressive strength than the masonry units will not “give,” thus causing stresses to be relieved through the masonry units–resulting in permanent damage to the masonry, such as cracking and spalling, that cannot be repaired easily. While stresses can also break the bond between the mortar and the masonry units, permitting water to penetrate the resulting hairline cracks, this is easier to correct in the joint through repointing than if the break occurs in the masonry units. Permeability, or rate of vapor transmission, is also critical. High lime mortars are more permeable than denser cement mortars. Historically, mortar acted as a bedding material–not unlike an expansion joint–rather than a “glue” for the masonry units, and moisture was able to migrate through the mortar joints rather than the masonry units. When moisture evaporates from the masonry it deposits any soluble salts either on the surface as efflorescence or below the surface as subflorescence. While salts deposited on the surface of masonry units are usually relatively harmless, salt crystallization within a masonry unit creates pressure that can cause parts ofthe outer surface to spall off or delaminate. If the mortar does not permitmoisture or moisture vapor to migrate out of the wall and evaporate, theresult will be damage to the masonry units. Components of Mortar Sand. Sand is the largest component of mortar and the material that gives mortar its distinctive color, texture and cohesiveness. Sand must be free of impurities, such as salts or clay. The three key characteristics of sand are: particle shape, gradation and void ratios. When viewed under a magnifying glass or low-power microscope, particles of sand generally have either rounded edges, such as found in beach and river sand, or sharp, angular edges, found in crushed or manufactured sand. For repointing mortar, rounded or natural sand is preferred for two reasons. It is usually similar to the sand in the historic mortar and provides a better visual match. It also has better working qualities or plasticity and can thus be forced into the joint more easily, forming a good contact with the remaining historic mortar and the surface of the adjacent masonry units. Although manufactured sand is frequently more readily available, it is usually possible to locate a supply of rounded sand. The gradation of the sand (particle size distribution) plays a very important role in the durability and cohesive properties of a mortar. Mortar must have a certain percentage of large to small particle sizes in order to deliver the optimum performance. Acceptable guidelines on particle size distribution may be found in ASTM C 144 (American Society for Testing and Materials). However, in actuality, since neither historic nor modern sands are always in compliance with ASTM C 144, matching the same particle appearance and gradation usually requires sieving the sand. A scoop of sand contains many small voids between the individual grains. A mortar that performs well fills all these small voids with binder (cement/lime combination or mix) in a balanced manner. Well-graded sand generally has a 30 per cent void ratio by volume. Thus, 30 per cent binder by volume generally should be used, unless the historic mortar had a different binder: aggregate ratio. This represents the 1:3 binder to sand ratios often seen in mortar specifications. For repointing, sand generally should conform to ASTM C 144 to assure proper gradation and freedom from impurities; some variation may be necessary to match the original size and gradation. Sand color and texture also should match the original as closely as possible to provide the proper color match without other additives. Lime. Mortar formulations prior to the late-19th century used lime as the primary binding material. Lime is derived from heating limestone at high temperatures which burns off the carbon dioxide, and turns the limestone into quicklime. There are three types of limestone–calcium, magnesium, and dolomitic–differentiated by the different levels of magnesium carbonate they contain which impart specific qualities to mortar. Historically, calcium lime was used for mortar rather than the dolomitic lime (calcium magnesium carbonate) most often used today. But it is also important to keep in mind the fact that the historic limes, and other components of mortar, varied a great deal because they were natural, as opposed to modern lime which is manufactured and, therefore, standardized. Because some of the kinds of lime, as well as other components of mortar, that were used historically are no longer readily available, even when a conscious effort is made to replicate a “historic” mix, this may not be achievable due to the differences between modern and historic materials. Lime, itself, when mixed with water into a paste is very plastic and creamy. It will remain workable and soft indefinitely, if stored in a sealed container. Lime (calcium hydroxide) hardens by carbonation absorbing carbon dioxide primarily from the air, converting itself to calcium carbonate. Once a lime and sand mortar is mixed and placed in a wall, it begins the process of carbonation. If lime mortar is left to dry too rapidly, carbonation of the mortar will be reduced, resulting in poor adhesion and poor durability. In addition, lime mortar is slightly water soluble and thus is able to re-seal any hairline cracks that may develop during the life of the mortar. Lime mortar is soft, porous, and changes little in volume during temperature fluctuations thus making it a good choice for historic buildings. Because of these qualities, high calcium lime mortar may be considered for many repointing projects, not just those involving historic buildings. For repointing, lime should conform to ASTM C 207, Type S, or Type SA, Hydrated Lime for Masonry Purposes. This machine-slaked lime is designed to assure high plasticity and water retention. The use of quicklime which must be slaked and soaked by hand may have advantages over hydrated lime in some restoration projects if time and money allow. Lime putty. Lime putty is slaked lime that has a putty or paste-like consistency. It should conform to ASTM C 5. Mortar can be mixed using lime putty according to ASTM C 270 property or proportion specification. Portland cement. More recent, 20th-century mortar has used portland cement as a primary binding material. A straight portland cement and sand mortar is extremely hard, resists the movement of water, shrinks upon setting, and undergoes relatively large thermal movements. When mixed with water, portland cement forms a harsh, stiff paste that is quite unworkable, becoming hard very quickly. (Unlike lime, portland cement will harden regardless of weather conditions and does not require wetting and drying cycles.) Some portland cement assists the workability and plasticity of the mortar without adversely affecting the finished project; it also provides early strength to the mortar and speeds setting. Thus, it may be appropriate to add some portland cement to an essentially lime-based mortar even when repointing relatively soft 18th or 19th century brick under some circumstances when a slightly harder mortar is required. The more portland cement that is added to a mortar formulation the harder it becomes–and the faster the initial set. For repointing, portland cement should conform to ASTM C 150. White, non- staining portland cement may provide a better color match for some historic mortars than the more commonly available grey portland cement. But, it should not be assumed, however, that white portland cement is always appropriate for all historic buildings, since the original mortar may have been mixed with grey cement. The cement should not have more than 0.60 per cent alkali to help avoid efflorescence. Masonry cement. Masonry cement is a preblended mortar mix commonly found at hardware and home repair stores. It is designed to produce mortars with a compressive strength of 750 psi or higher when mixed with sand and water at the job site. It may contain hydrated lime, but it always contains a large amount of portland cement, as well as ground limestone and other workability agents, including air-entraining agents. Because masonry cements are not required to contain hydrated lime, and generally do not contain lime, they produce high strength mortars that can damage historic masonry. For this reason, they generally are not recommended for use on historic masonry buildings. Lime mortar (pre-blended). Hydrated lime mortars, and pre-blended lime putty mortars with or without a matched sand are commercially available. Custom mortars are also available with color. In most instances, pre-blended lime mortars containing sand may not provide an exact match; however, if the project calls for total repointing, a pre-blended lime mortar may be worth considering as long as the mortar is compatible in strength with the masonry. If the project involves only selected, “spot” repointing, then it may be better to carry out a mortar analysis which can provide a custom pre-blended lime mortar with a matching sand. In either case, if a preblended lime mortar is to be used, it should contain Type S or SA hydrated lime conforming to ASTM C 207. Water. Water should be potable–clean and free from acids, alkalis, or other dissolved organic materials. Other Components Historic components. In addition to the color of the sand, the texture of the mortar is of critical importance in duplicating historic mortar. Most mortars dating from the mid-19th century on–with some exceptions–have a fairly homogeneous texture and color. Some earlier mortars are not as uniformly textured and may contain lumps of partially burned lime or “dirty lime”, shell (which often provided a source of lime, particularly in coastal areas), natural cements, pieces of clay, lampblack or other pigments, or even animal hair. The visual characteristics of these mortars can be duplicated through the use of similar materials in the repointing mortar. Replicating such unique or individual mortars will require writing new specifications for each project. If possible, suggested sources for special materials should be included. For example, crushed oyster shells can be obtained in a variety of sizes from poultry supply dealers. Pigments. Some historic mortars, particularly in the late 19th century, were tinted to match or contrast with the brick or stone (Fig. 6). Red pigments, sometimes in the form of brick dust, as well as brown, and black pigments were commonly used. Modern pigments are available which can be added to the mortar at the job site, but they should not exceed 10 per cent by weight of the portland cement in the mix, and carbon black should be limited to 2 per cent. Only synthetic mineral oxides, which are alkali-proof and sun- fast, should be used to prevent bleaching and fading. Modern components. Admixtures are used to create specific characteristics in mortar, and whether they should be used will depend upon the individual project. Air entraining agents, for example, help the mortar to resist freeze-thaw damage in northern climates. Accelerators are used to reduce mortar freezing prior to setting while retarders help to extend the mortar life in hot climates. Selection of admixtures should be made by the architect or architectural conservator as part of the specifications, not something routinely added by the masons. Generally, modern chemical additives are unnecessary and may, in fact, have detrimental effects in historic masonry projects. The use of antifreeze compounds is not recommended. They are not very effective with high lime mortars and may introduce salts, which may cause efflorescence later. A better practice is to warm the sand and water, and to protect the completed work from freezing. No definitive study has determined whether air-entraining additives should be used to resist frost action and enhance plasticity, but in areas of extreme exposure requiring high-strength mortars with lower permeability, air-entrainment of 10-16 percent may be desirable (see formula for “severe weather exposure” in Mortar Type and Mix). Bonding agents are not a substitute for proper joint preparation, and they should generally be avoided. If the joint is properly prepared, there will be a good bond between the new mortar and the adjacent surfaces. In addition, a bonding agent is difficult to remove if smeared on a masonry surface. Mortar Type and Mix Mortars for repointing projects, especially those involving historic buildings, typically are custom mixed in order to ensure the proper physical and visual qualities. These materials can be combined in varying proportions to create a mortar with the desired performance and durability. The actual specification of a particular mortar type should take into consideration all of the factors affecting the life of the building including: current site conditions, present condition of the masonry, function of the new mortar, degree of weather exposure, and skill of the mason. Thus, no two repointing projects are exactly the same. Modern materials specified for use in repointing mortar should conform to specifications of the American Society for Testing and Materials (ASTM) or comparable federal specifications, and the resulting mortar should conform to ASTM C 270, Mortar for Unit Masonry. Specifying the proportions for the repointing mortar for a specific job is not as difficult as it might seem. Five mortar types, each with a corresponding recommended mix, have been established by ASTM to distinguish high strength mortar from soft flexible mortars. The ASTM designated them in decreasing order of approximate general strength as Type M (2,500 psi), Type S (1,800 psi), Type N (750 psi), Type O (350 psi) and Type K (75 psi). (The letters identifying the types are from the words MASON WORK using every other letter.) Type K has the highest lime content of the mixes that contain portland cement, although it is seldom used today, except for some historic preservation projects. The designation “L” in the accompanying chart identifies a straight lime and sand mix. Specifying the appropriate ASTM mortar by proportion of ingredients, will ensure the desired physical properties. Unless specified otherwise, measurements or proportions for mortar mixes are always given in the following order: cement-lime-sand. Thus, a Type K mix, for example, would be referred to as 1-3-10, or 1 part cement to 3 parts lime to 10 parts sand. Other requirements to create the desired visual qualities should be included in the specifications. The strength of a mortar can vary. If mixed with higher amounts of portland cement, a harder mortar is obtained. The more lime that is added, the softer and more plastic the mortar becomes, increasing its workability. A mortar strong in compressive strength might be desirable for a hard stone (such as granite) pier holding up a bridge deck, whereas a softer, more permeable lime mortar would be preferable for a historic wall of soft brick. Masonry deterioration caused by salt deposition results when the mortar is less permeable than the masonry unit. A strong mortar is still more permeable than hard, dense stone. However, in a wall constructed of soft bricks where the masonry unit itself has a relatively high permeability or vapor transmission rate, a soft, high lime mortar is necessary to retain sufficient permeability. Budgeting and Scheduling Repointing is both expensive and time consuming due to the extent of handwork and special materials required. It is preferable to repoint only those areas that require work rather than an entire wall, as is often specified. But, if 25 to 50 per cent or more of a wall needs to be repointed, repointing the entire wall may be more cost effective than spot repointing. Total repointing may also be more sensible when access is difficult, requiring the erection of expensive scaffolding (unless the majority of the mortar is sound and unlikely to require replacement in the foreseeable future). Each project requires judgement based on a variety of factors. Recognizing this at the outset will help to prevent many jobs from becoming prohibitively expensive. In scheduling, seasonal aspects need to be considered first. Generally speaking, wall temperatures between 40 and 95 degrees F (8 and 38 degrees C) will prevent freezing or excessive evaporation of the water in the mortar. Ideally, repointing should be done in shade, away from strong sunlight in order to slow the drying process, especially during hot weather. If necessary, shade can be provided for large-scale projects with appropriate modifications to scaffolding. The relationship of repointing to other work proposed on the building must also be recognized. For example, if paint removal or cleaning is anticipated, and if the mortar joints are basically sound and need only selective repointing, it is generally better to postpone repointing until after completion of these activities. However, if the mortar has eroded badly, allowing moisture to penetrate deeply into the wall, repointing should be accomplished before cleaning. Related work, such as structural or roof repairs, should be scheduled so that they do not interfere with repointing and so that all work can take maximum advantage of erected scaffolding. Building managers also must recognize the difficulties that a repointing project can create. The process is time consuming, and scaffolding may need to remain in place for an extended period of time. The joint preparation process can be quite noisy and can generate large quantities of dust which must be controlled, especially at air intakes to protect human health, and also where it might damage operating machinery. Entrances may be blocked from time to time making access difficult for both building tenants and visitors. Clearly, building managers will need to coordinate the repointing work with other events at the site. Contractor Selection The ideal way to select a contractor is to ask knowledgeable owners of recently repointed historic buildings for recommendations. Qualified contractors then can provide lists of other repointing projects for inspection. More commonly, however, the contractor for a repointing project is selected through a competitive bidding process over which the client or consultant has only limited control. In this situation it is important to ensure that the specifications stipulate that masons must have a minimum of five years’ experience with repointing historic masonry buildings to be eligible to bid on the project. Contracts are awarded to the lowest responsible bidder, and bidders who have performed poorly on other projects usually can be eliminated from consideration on this basis, even if they have the lowest prices. The contract documents should call for unit prices as well as a base bid. Unit pricing forces the contractor to determine in advance what the cost addition or reduction will be for work which varies from the scope of the base bid. If, for example, the contractor has fifty linear feet less of stone repointing than indicated on the contract documents but thirty linear feet more of brick repointing, it will be easy to determine the final price for the work. Note that each type of work–brick repointing, stone repointing, or similar items–will have its own unit price. The unit price also should reflect quantities; one linear foot of pointing in five different spots will be more expensive than five contiguous linear feet. Execution of the Work Test Panels. These panels are prepared by the contractor using the same techniques that will be used on the remainder of the project. Several panel locations–preferably not on the front or other highly visible location of the building–may be necessary to include all types of masonry, joint styles, mortar colors, and other problems likely to be encountered on the job. If cleaning tests, for example, are also to be undertaken, they should be carried out in the same location. Usually a 3 foot by 3 foot area is sufficient for brickwork, while a somewhat larger area may be required for stonework. These panels establish an acceptable standard of work and serve as a benchmark for evaluating and accepting subsequent work on the building. Joint Preparation. Old mortar should be removed to a minimum depth of 2 to 2-1/2 times the width of the joint to ensure an adequate bond and to prevent mortar “popouts.” For most brick joints, this will require removal of the mortar to a depth of approximately to 1 inch; for stone masonry with wide joints, mortar may need to be removed to a depth of several inches. Any loose or disintegrated mortar beyond this minimum depth also should be removed. Although some damage may be inevitable, careful joint preparation can help limit damage to masonry units. The traditional manner of removing old mortar is through the use of hand chisels and mash hammers. Though labor-intensive, in most instances this method poses the least threat for damage to historic masonry units and produces the best final product. The most common method of removing mortar, however, is through the use of power saws or grinders. The use of power tools by unskilled masons can be disastrous for historic masonry, particularly soft brick. Using power saws on walls with thin joints, such as most brick walls, almost always will result in damage to the masonry units by breaking the edges and by overcutting on the head, or vertical joints. However, small pneumatically-powered chisels generally can be used safely and effectively to remove mortar on historic buildings as long as the masons maintain appropriate control over the equipment. Under certain circumstances, thin diamond-bladed grinders may be used to cut out horizontal joints only on hard portland cement mortar common to most early-20th century masonry buildings. Usually, automatic tools most successfully remove old mortar without damaging the masonry units when they are used in combination with hand tools in preparation for repointing. Where horizontal joints are uniform and fairly wide, it may be possible to use a power masonry saw to assist the removal of mortar, such as by cutting along the middle of the joint; final mortar removal from the sides of the joints still should be done with a hand chisel and hammer. Caulking cutters with diamond blades can sometimes be used successfully to cut out joints without damaging the masonry. Caulking cutters are slow; they do not rotate, but vibrate at very high speeds, thus minimizing the possibility of damage to masonry units. Although mechanical tools may be safely used in limited circumstances to cut out horizontal joints in preparation for repointing, they should never be used on vertical joints because of the danger of slipping and cutting into the brick above or below the vertical joint. Using power tools to remove mortar without damaging the surrounding masonry units also necessitates highly skilled masons experienced in working on historic masonry buildings. Contractors should demonstrate proficiency with power tools before their use is approved. Using any of these power tools may also be more acceptable on hard stone, such as quartzite or granite, than on terra cotta with its glass-like glaze, or on soft brick or stone. The test panel should determine the acceptability of power tools. If power tools are to be permitted, the contractor should establish a quality control program to account for worker fatigue and similar variables. Mortar should be removed cleanly from the masonry units, leaving square corners at the back of the cut. Before filling, the joints should be rinsed with a jet of water to remove all loose particles and dust. At the time of filling, the joints should be damp, but with no standing water present. For masonry walls–limestone, sandstone and common brick–that are extremely absorbent, it is recommended that a continual mist of water be applied for a few hours before repointing begins. Mortar Preparation. Mortar components should be measured and mixed carefully to assure the uniformity of visual and physical characteristics. Dry ingredients are measured by volume and thoroughly mixed before the addition of any water. Sand must be added in a damp, loose condition to avoid over sanding. Repointing mortar is typically pre-hydrated by adding water so it will just hold together, thus allowing it to stand for a period of time before the final water is added. Half the water should be added, followed by mixing for approximately 5 minutes. The remaining water should then be added in small portions until a mortar of the desired consistency is reached. The total volume of water necessary may vary from batch to batch, depending on weather conditions. It is important to keep the water to a minimum for two reasons: first, a drier mortar is cleaner to work with, and it can be compacted tightly into the joints; second, with no excess water to evaporate, the mortar cures without shrinkage cracks. Mortar should be used within approximately 30 minutes of final mixing, and “retempering,” or adding more water, should not be permitted. Using Lime Putty to Make Mortar. Mortar made with lime putty and sand, sometimes referred to as roughage or course stuff, should be measured by volume, and may require slightly different proportions from those used with hydrated lime. No additional water is usually needed to achieve a workable consistency because enough water is already contained in the putty. Sand is proportioned first, followed by the lime putty, then mixed for five minutes or until all the sand is thoroughly coated with the lime putty. But mixing, in the familiar sense of turning over with a hoe, sometimes may not be sufficient if the best possible performance is to be obtained from a lime putty mortar. Although the old practice of chopping, beating and ramming the mortar has largely been forgotten, recent field work has confirmed that lime putty and sand rammed and beaten with a wooden mallet or ax handle, interspersed by chopping with a hoe, can significantly improve workability and performance. The intensity of this action increases the overall lime/sand contact and removes any surplus water by compacting the other ingredients. It may also be advantageous for larger projects to use a mortar pan mill for mixing. Mortar pan mills which have a long tradition in Europe produce a superior lime putty mortar not attainable with today’s modern paddle and drum type mixers. For larger repointing projects the lime putty and sand can be mixed together ahead of time and stored indefinitely, on or off site, which eliminates the need for piles of sand on the job site. This mixture, which resembles damp brown sugar, must be protected from the air in sealed containers with a wet piece of burlap over the top or sealed in a large plastic bag to prevent evaporation and premature carbonation. The lime putty and sand mixture can be recombined into a workable plastic state months later with no additional water. If portland cement is specified in a lime putty and sand mortar–Type O (1:2:9) or Type K (1:3:11)–the portland cement should first be mixed into a slurry paste before adding it to the lime putty and sand. Not only will this ensure that the portland cement is evenly distributed throughout the mixture, but if dry portland cement is added to wet ingredients it tends to “ball up,” jeopardizing dispersion. (Usually water must be added to the lime putty and sand anyway once the portland cement is introduced.) Any color pigments should be added at this stage and mixed for a full five minutes. The mortar should be used within 30 minutes to 1 hours and it should not be retempered. Once portland cement has been added the mortar can no longer be stored. Filling the Joint. Where existing mortar has been removed to a depth of greater than 1 inch, these deeper areas should be filled first, compacting the new mortar in several layers. The back of the entire joint should be filled successively by applying approximately 1/4 inch of mortar, packing it well into the back corners. This application may extend along the wall for several feet. As soon as the mortar has reached thumb-print hardness, another 1/4 inch layer of mortar–approximately the same thickness–may be applied. Several layers will be needed to fill the joint flush with the outer surface of the masonry. It is important to allow each layer time to harden before the next layer is applied; most of the mortar shrinkage occurs during the hardening process and layering thus minimizes overall shrinkage. When the final layer of mortar is thumb-print hard, the joint should be tooled to match the historic joint. Proper timing of the tooling is important for uniform color and appearance. If tooled when too soft, the color will be lighter than expected, and hairline cracks may occur; if tooled when too hard, there may be dark streaks called “tool burning,” and good closure of the mortar against the masonry units will not be achieved. If the old bricks or stones have worn, rounded edges, it is best to recess the final mortar slightly from the face of the masonry. This treatment will help avoid a joint which is visually wider than the actual joint; it also will avoid creation of a large, thin featheredge which is easily damaged, thus admitting water. After tooling, excess mortar can be removed from the edge of the joint by brushing with a natural bristle or nylon brush. Metal bristle brushes should never be used on historic masonry. Curing Conditions. The preliminary hardening of high-lime content mortars–those mortars that contain more lime by volume than portland cement, i.e., Type O (1:2:9), Type K (1:3:11), and straight lime/sand, Type “L” (0:1:3)–takes place fairly rapidly as water in the mix is lost to the porous surface of the masonry and through evaporation. A high lime mortar (especially Type “L”) left to dry out too rapidly can result in chalking, poor adhesion, and poor durability. Periodic wetting of the repointed area after the mortar joints are thumb-print hard and have been finish tooled may significantly accelerate the carbonation process. When feasible, misting using a hand sprayer with a fine nozzle can be simple to do for a day or two after repointing. Local conditions will dictate the frequency of wetting, but initially it may be as often as every hour and gradually reduced to every three or four hours. Walls should be covered with burlap for the first three days after repointing. (Plastic may be used, but it should be tented out and not placed directly against the wall.) This helps keep the walls damp and protects them from direct sunlight. Once carbonation of the lime has begun, it will continue for many years and the lime will gain strength as it reverts back to calcium carbonate within the wall. Aging the Mortar. Even with the best efforts at matching the existing mortar color, texture, and materials, there will usually be a visible difference between the old and new work, partly because the new mortar has been matched to the unweathered portions of the historic mortar. Another reason for a slight mismatch may be that the sand is more exposed in old mortar due to the slight erosion of the lime or cement. Although spot repointing is generally preferable and some color difference should be acceptable, if the difference between old and new mortar is too extreme, it may be advisable in some instances to repoint an entire area of a wall, or an entire feature such as a bay, to minimize the difference between the old and the new mortar. If the mortars have been properly matched, usually the best way to deal with surface color differences is to let the mortars age naturally. Other treatments to overcome these differences, including cleaning the non-repointed areas or staining the new mortar, should be carefully tested prior to implementation. Staining the new mortar to achieve a better color match is generally not recommended, but it may be appropriate in some instances. Although staining may provide an initial match, the old and new mortars may weather at different rates, leading to visual differences after a few seasons. In addition, the mixtures used to stain the mortar may be harmful to the masonry; for example, they may introduce salts into the masonry which can lead to efflorescence. Cleaning the Repointed Masonry. If repointing work is carefully executed, there will be little need for cleaning other than to remove the small amount of mortar from the edge of the joint following tooling. This can be done with a stiff natural bristle or nylon brush after the mortar has dried, but before it is initially set (1-2 hours). Mortar that has hardened can usually be removed with a wooden paddle or, if necessary, a chisel. Further cleaning is best accomplished with plain water and natural bristle or nylon brushes. If chemicals must be used, they should be selected with extreme caution. Improper cleaning can lead to deterioration of the masonry units, deterioration of the mortar, mortar smear, and efflorescence. New mortar joints are especially susceptible to damage because they do not become fully cured for several months. Chemical cleaners, particularly acids, should never be used on dry masonry. The masonry should always be completely soaked once with water before chemicals are applied. After cleaning, the walls should be flushed again with plain water to remove all traces of the chemicals. Several precautions should be taken if a freshly repointed masonry wall is to be cleaned. First, the mortar should be fully hardened before cleaning. Thirty days is usually sufficient, depending on weather and exposure; as mentioned previously, the mortar will continue to cure even after it has hardened. Test panels should be prepared to evaluate the effects of different cleaning methods. Generally, on newly repointed masonry walls, only very low pressure (100 psi) water washing supplemented by stiff natural bristle or nylon brushes should be used, except on glazed or polished surfaces, where only soft cloths should be used.** New construction “bloom” or efflorescence occasionally appears within the first few months of repointing and usually disappears through the normal process of weathering. If the efflorescence is not removed by natural processes, the safest way to remove it is by dry brushing with stiff natural or nylon bristle brushes followed by wet brushing. Hydrochloric (muriatic) acid, is generally ineffective, and it should not be used to remove efflorescence. It may liberate additional salts, which, in turn, can lead to more efflorescence. Surface Grouting is sometimes suggested as an alternative to repointing brick buildings, in particular. This process involves the application of a thin coat of cement-based grout to the mortar joints and the mortar/brick interface. To be effective, the grout must extend slightly onto the face of the masonry units, thus widening the joint visually. The change in the joint appearance can alter the historic character of the structure to an unacceptable degree. In addition, although masking of the bricks is intended to keep the grout off the remainder of the face of the bricks, some level of residue, called “veiling,” will inevitably remain. Surface grouting cannot substitute for the more extensive work of repointing, and it is not a recommended treatment for historic masonry.

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A low maintenance and durable material, vinyl siding is an increasingly popular home exterior. Even though it is a low maintenance material, you will still want to clean your vinyl siding from time to time. Just make sure you know about the best cleaning methods before you get started. Simple maintenance cleaning of your vinyl siding is fairly straightforward. Use a long-handled brush with soft bristles or a soft cloth to wipe it down with soap and water. If your vinyl siding has textured surfaces to it, you will want to use only the brush with soft bristles so as to avoid wiping stains into the grooves with a cloth. Start with the vinyl siding at the bottom of your house and work your way up. This will help to prevent streaking from the soapy water running down your house. If you have other materials, such as brick, on parts of your home, cover them so that runoff from your vinyl siding will not affect it. Lastly, always make sure you rinse the area before the cleaning solution dries. If you want to speed the process of cleaning your vinyl siding along, you can buy or rent a power washer. First of all, however, make sure you have read the instructions on the power washer thoroughly. Second, always make sure you use the power washer at eye level. If you try to point upward, you may end up with water and cleaning solution behind the vinyl siding. These can later leak and cause streaks that can eventually lead to decay. From time to time, you may find spots of mold or mildew on your vinyl siding. If these spots are small, then you can simply use a name brand household cleaner. Just always be sure to test it on a small portion of your vinyl siding in an inconspicuous place to make sure it will not damage it at all. If, however, the spots of mold or mildew are a little larger, you can use a solution of 30% vinegar and 70% water. Another common homemade solution is mixture of powdered laundry detergent, powdered household cleaner, liquid bleach, and water. It is best to just find the one that is most convenient and effective for you. Not all vinyl siding stains, however, are mold or mildew. You may end up with dirt, soot, or even animal stains on the outside of your home. If that is the case, there are a number of general cleaners that are approved for use on vinyl siding. Check your local store for simple household cleaners, and then read the containers carefully to find out if they are effective and safe for use on vinyl siding and specifically on whatever the stain is that you have found on your vinyl siding. Increasingly, vinyl siding is a common home exterior. It is low maintenance, attractive, and easy to install. You may, though, from time to time need to clean your vinyl siding in order to keep it in good working condition. Before you do, make sure you understand what is necessary and what the proper procedure is so that your vinyl siding will look good and last a long time.

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Polyurethane Foams for Low Pressure Injection Crack Repair

What is the better choice: polyurethane or epoxy? Epoxy is the better choice if structural strength is required to be maintained. If the crack is only repaired to prevent water leakage then either product can accomplish this task.

Cause of Cracks

Lack of joints, to accommodate drying shrinkage and thermal movement during the construction phase is one of the major causes of concrete cracks. Settlement and overloading are also common causes of cracking. Cracks usually appear within the first month after construction. These cracks can leak as soon as they are formed or might expand and leak later. Crack can grow and cause problems as they expand.

How Cracks Grow

Moisture, which is the worst enemy of homes, enters the tiny cracks in the concrete and in colder weather, freezes, enlarging the crack. Also, movement of soils surrounding your home, through settling, can also cause expansion of your cracks. In extreme cases, soils that are unstable can overcome the inherent strength of concrete causing crack and expansion.

Cracks caused by construction, heat, freezing and settlement can be corrected by injection. Cracks caused by unstable soils must have soil problem stabilized prior to attempting injection corrective methods.

Low Pressure Injection

This method of injecting polymers into the concrete is adequate for repairs of cracks not involving high volumes of water. High-pressure injection is better suited for this type of application. Low pressure is defined as injection pressures between 20 to 40 psi and can be used with either ports or surface injection. Pressures as high as 250 psi may be used.

High Pressure Injection

1,000 to 10,000 psi utilizing injection packers usually placed in holes drilled at 45 degrees to intersect the interior of the crack. This is common method of repair using polyurethane foam. High cost of packers, clean up of excess, potential stress damage and dangers of using high pressure are overcome by using low-pressure injection methods.

The use of surface ports (with one-way check valves) together with low-pressure injection of a sealed crack eliminates these problems in most situations. The injection of high-density foam is an effective water proofing method.

The best method for low-pressure crack repair is to slowly inject liquid polymer into crack until crack is completely filled, filling of adjacent surface port is visual confirmation. Using pressures above the 40-psi will allow polymer to rise and may indicate a false presence of the polymer filling voids.

Methods of Surface Sealing and Placing of Surface Ports

Surfaces are first cleaned with wire brush, and then surface ports are placed along crack at intervals equal to the thickness of the wall. The surface crack is then filled with epoxy paste which when sufficiently hardened allows filling of surface ports to begin. Hydraulic cement is used when cracks are actively “wet”. The ports must then be anchored to prevent blowing off during injection.

Types of Epoxies

Epoxies for crack injection vary in viscosities to suit the width of crack to be filled. Whatever viscosity chosen, the applicator has to ensure that he can keep injection pressure less than 40 psi to ensure complete coverage of cracks and voids.

Injecting Polyurethane Foam

Polyurethane elastomeric foams are effective for water proofing cracks and where structural repair is not required. These products are flexible enough to move with concrete and maintain seal. These foams can be used where there is active water flow and mix with water, combined with foaming action, effectively stop water infiltration.

The rapid thickening of foam products makes it possible to remove surface seal and surface ports a couple of hours after injection. This also prevents and minimizes leakage out the back of repair area, which may not be accessible.

Polyurethane foams are classed as hydrophilic or hydrophobic. They both react with water, either in the crack or mixed prior to injection. The hydrophilic system is typically more resilient than that of the hydrophobic foams. Hydrophilic foam can lose its excess water due to dry conditions and subsequently shrink. The hydrophobic product is reputed to be impervious to shrinkage through drying.

Dual Cartridge Dispensing

This method has simplified the injection application allowing for fast inexpensive injection of cracks. Clean up is virtually eliminated and maintenance is bare minimum. This method is usually used when less than 5 gallons of material is required.

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Most water problems that homeowners encounter can usually be by controlling water above ground. Simple but effective means of controlling those above-ground problems may prevent structural damage to your home as well as dry up those basement damp areas. Most home owners are un-aware that saturated soil increases the soil pressure on the basement wall which can the lead to cracks, shifts, collapses and other structural problems. Start first by looking to the roof,. An inch of water on 1,000 square feet of roof amounts to about 623 gallons of water. A foot of compacted snow on that same roof could contain up to 4 inches of water, or nearly 2,500 gallons. Getting all that water away from the house is a big first step to preventing basement problems and can prevent needless costs in repairs. Ensuring your eaves trough have extension or splash pads that adequately remove water from around your house is the first step in preventing water intrusion or damage to your home. A slope of about 1 inch per foot drainage near the foundation wall is usually adequate. Also, the ground should be sloped to carry the water away from the downspout discharge.

In addition to proper drainage above ground, a properly installed drainage system below ground is important to keeping your basement dry. A properly installed drainage system at the house foundation will prevent many water problems from entering your basement and eliminate saturated soil conditions next to the wall. A study of leakage problems showed that more than 90 percent were due to improperly installed drainage systems. The engineer says a properly installed foundation drainage system includes drainpipes placed alongside the footing. In areas with high water tables, a drainage system can also be installed around the inside of the footing and under the basement floor. Using granular material to allow the movement of water and filtering material to keep soil from plugging drain pipes is essential to keeping the system functioning for the life of the house. Granular backfill should be used next to basement walls, he notes. Using soils that don’t drain well can cause pressure on the walls if the soils become saturated. Most contractors now use a dimpled wrap installed against the foundation ensuring water drains down to weeping tile thus preventing hydraulic pressure from building against foundation walls. Poor drainage will also increase the potential for moisture or water vapor to move through the wall into the basement.

In certain areas, that moisture can carry minerals that are detrimental to the concrete. Basement walls that have had water or moisture leaks will usually leave an effervescent stain which is typically non-removable. Homeowners and home inspectors always view effervescence as indication of water penetration.

Window wells also need to be correctly constructed with drains linked to the foundation drains. Soil elevation in the window well should be several inches below bottom of window and sloped to the drain. The cost of installing the drainage system during new construction is minimal and is minimum building code requirement.

Window drains are usually installed in two ways; one is to place window well drain on top of foundation weeping tile and then fill with clean stone, thereby preventing entry and possible blockage from debris; two is to connect window well drain with Tee into foundation weeping tile and close off top of window drain with mesh sock or other means of preventing debris entry. As a home inspector I find many window well drains that are open and partially filled with leaves and toys etc. A blocked window well drain will allow build-up of water in heavy rain or snow melt and could enter basement windows.

Many homes have in-ground drains for roof drainage discharge. These usually work well in warm months but in winter they are prone to freezing. I always recommend to my clients that they install a Tee at the top of ground drain which will serve as run off if ground drain is frozen but water is melting on roof. As the ground is the last are to un-thaw water will back up downspout and then freeze at night, installing a Tee will prevent this.

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Primarily in the 1960s and 1970s, many electrical contractors used aluminum wiring instead of copper wiring as a way to save money and lower construction costs. However, a number of electrical fires have been attributed to aluminum wiring. Many building codes have been rewritten to not allow the use of aluminum wire for branch circuit wiring in houses.

Copper vs. Aluminum — The Test Results are in! Tests have demonstrated aluminum wiring has inherent properties that make it more susceptible to fires when it was not installed correctly. Here are some of the problems with using aluminum wiring to conduct electricity. Aluminum does not conduct electricity as well as copper. An aluminum wire generates more heat. Aluminum is more brittle than copper. Wire is more likely to break or crimp if it is brittle. Arcing can occur if a wire breaks or crimps. This can cause very high temperatures inside the wall or ceiling Aluminum is more likely to corrode than copper. Aluminum will oxidize if it comes in contact with moisture. This oxidation removes the pure aluminum and makes the wire thinner. A thinner wire creates more heat when electrical current is running through it. Oxidation also causes the wire to expand, puts pressure on the protective plastic coating on the wire, and can cause the plastic to split. If any of these occur, arcing may result which can cause fires. Aluminum expands and contracts more than copper. This puts additional stress at all connections such as outlets and switches. If these become loose, arcing can occur at these points. If contemplating buying an older home with aluminum wiring or updating a home with aluminum wiring, contact a certified electrician to gain their expertise and opinion regarding the dangers of aluminum wiring.

State Farm believes the information contained in the Good Neighbor House is reliable and accurate. We cannot, however, guarantee the performance of all items demonstrated or described in all situations. Always consult an experienced contractor or other expert to determine the best application of these ideas or products in your home.
Between 1965 and 1973, aluminum wiring was used to install electrical branch circuits in about 1.5 million homes in the United States and Canada. Subsequent fires in some of these homes were attributed to faulty aluminum wire connections. During this period, studies conducted by the National Fire Protection Association, in conjunction with the U.S. Consumer Products Safety Commission, revealed that homes using aluminum wires manufactured before 1972 are 55 times more likely to have one or more electrical connections reach fire hazard condition than homes wired with copper. Aluminum wiring in itself is not dangerous. Aluminum wiring, when properly installed, can be just as safe as copper. But if it has not been installed properly, the connections-where the wires join to the outlets and switches- can present a fire hazard.

How to Tell The wiring that is of concern involves the circuit wiring to your outlets and light switches, and to appliances that us 115 volt current, such as furnace and washing machine. It is a single-strand, solid aluminum wire, silver in color as opposed to the characteristic copper wiring color. Most homes of any vintage employ some aluminum wiring. Often service entrance cables from the street that run to the distribution panel and major appliance circuits (220v) are aluminum. The safety concerns are not with the cables, but rather with branch circuit connections involving the lighting and other 115 v circuits. The Problem Most problems arise with solid aluminum wire, sizes #10 and #12 gauge. These problems concern the ends, or terminations, of the aluminum wire, where they connect under the bonding screws. If the connections are improperly installed, there is a potential for intermittent, hot connections where the wires join to the outlets and switches. Again, the problem is with the connections, and not with the wiring itself. The main difficulty with connections using aluminum wiring is a phenomenon known as cold creep. Aluminums coefficient of expansion (how much it expands when electrical current passes through it) is higher than coppers. Simply put, when aluminum wiring warms up, it expands more than copper does, and when it cools down, it contracts more than copper does. This expansion and contraction, over time, will allow for loosening at the connections. Also aluminum wire needs to be larger than copper to carry the same amount of electricity. Because the wires are thicker, you cannot get the same tightness at the connections. Therefore, they may loosen more quickly. To make the problem worse, all metals oxidize or corrode in an oxygen environment. Copper oxidation forms as a conductor, while aluminum develops as a resistor. This resistance causes heat. Oxidation accelerates when two unlike metals are in contact with each other. This may be part of the source of increased resistance when aluminum wire joins to outlets or switches intended for copper. Eventually the wire may start getting very hot, melt the insulation or fixture its attached to, and possibly even cause a fire. Evaluation of Your Electrical System As mentioned above, aluminum wiring can be just as safe as copper when properly installed. Denver’s Building Department has always maintained-including during the years 1965 to 1977, when aluminum wiring was being installed nationwide- a force of electrical inspectors who themselves are licensed electricians and have worked diligently to ensure that all installations comply with local and national standards. Many of the incidents publicized from other parts of the country simply don’t occur here. Still, any potential electrical problem is a potentially serious problem.

There are several warning signs to look for that would suggest the possibility of connection problems. They are:
- Sparks emanating from outlets
- Warm-to-touch cover plates on outlets and switches
- Smoke coming from outlets, junction boxes or switches
- Lights that flicker for no apparent reason
- Melted insulation (plastic) at the connections
- Smell of burning plastic at outlets
- Light bulbs that burn out quickly, or shine unusually bright
- Blown fuses or tripped breakers for no apparent reason
- The size of your television picture shrinks

Making Sure Its Safe
If you are experiencing one or more of the above connection problems, or are otherwise concerned, we suggest that you hire a licensed electrician to check over the wiring for the following:
1. Outlets and switches directly attached to aluminum wiring shall be listed for that purpose. The device will be stamped with AL/CU or CO/ALR. The latter supersedes the former, but both are safe. These fixtures are somewhat more expensive than the ordinary ones.
2. Wire should be properly connected (wrapped at least way around the screw in a clockwise direction). Connections should be tight. While repeated tightening of the screws can make the problem worse, during the inspection it would pay off to have the electrician snug up each connection.
3. Push-in terminals (terminals where the connecting wire is pushed into a slot rather than wound around a screw) are an extreme hazard with aluminum wire. Any connections using push-in terminals should be redone with the proper screw connections immediately. 4. There should be no signs of overheating darkened connections, melted insulation, or baked outlets or switches. Any such damage should be repaired.
5. Connections between aluminum and copper wire need to be handled specially. Current Denver City Ordinance requires that the connections used must be specially marked for connecting aluminum to copper. The National Electrical Code requires that the wire be a connected together using special crimp device, with antioxidant grease (see Repair Options, over).
6. National Electrical Code, Sections 110-114 and 310-314 address electrical conductors of dissimilar metals and prohibit the use of unlisted twist-on connectors for connection of copper and aluminum wiring.

A Final Caution The United States Fire Administration reports that annually, of the nearly 800,000 residential fire nationwide, approximately 75,000 began in the homes electrical distribution system that is, in the circuit wiring, receptacles, switches, cords and plugs. When a part of this network fails or is misused, a fire may result. Many of these fires were attributed to old technology aluminum branch circuit wiring. Of the fires involving old technology aluminum branch circuit wiring, 75 percent of the incidents involved receptacles, 12 percent involved panel equipment terminals, and 10 percent involved twist-on connections. Fire investigators, including those of the Denver Fire Departments Fire Prevention and Investigation Division, determined that old technology aluminum-wired receptacles and twist-on connectors, when used with aluminum wire, were failure prone, even when installed carefully in accordance with the manufacturers instructions. Leave aluminum wiring safety improvements to licensed electrical contractors. Denvor Building Department electrical inspectors will monitor work done under City permit. Any time you suspect unusual heat or smoke generated from the electrical system in your house, do not hesitate to call 911 and request a Fire Company to respond and evaluate conditions. The safety of your family is of primary importance.

This article by the Denver Fire Department is brought to you by Napoleon Home Inspections – The Barrie Home Inspector

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