Exterior Windows

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Windows provide natural light and ventilation and are classified by the method by which they open and close (e.g. casement window). Windows are made from wood, steel, aluminum, vinyl, vinyl-clad wood or aluminum. Some modern windows have a thermal break, usually Bakelite, between the interior and exterior part of the window to prevent condensation build up during the winter months.

Most insulated glass units are double or triple-pane windows that are sealed with an epoxy to create an air gap between each plate of glass. The window frame is perforated on the inside and filled with a desiccant material that absorbs the moisture vapors from between the glass plates. The wider the dry air space, the greater the insulating value of the unit. Some manufacturers also use a coating over the glass for greater energy efficiency. The coating is often called low-emissivity or low E glass. Low E glass reflects radiant heat in the summer and retains interior heat in the winter. Very few manufacturers hermetically seal or create a dry air gap between the panes and then use an air tight seal.

In the winter if you leave your drapes or blinds closed you will notice a build up of condensation on the interior surface of your window. This is caused when your window covering prevents heat from warming the interior surface of the window and the "Dew Point", (the temperature at which humidity in the air turns to condensation) moves from the exterior to the interior surface of the window. If windows are left covered for long periods of time, water can actually pool on your window ledges, expecially in the fall when there is still a lot of humidity in the air.

Window Defects

Leaking Thermal Seal

Thermal seal windows can develop leaks in the seal between the panes of glass. Twisting of casement windows or even the hot sun can cause a seal to leak. In cold weather there will be noticeable condensation between the panes of glass and if the interior frame is metal, rusting will occur. The only logical repair is to have the thermal unit replaced. There are companies that will drill holes in your glass and clean the interior but the saving is not enough to warrant this cheaper alternative to replacing the unit.

Crack in Skylight

Skylight on roof has crack in plexiglass material. Although crack was not visible from inside the house, during roof inspection it was readily visible. Skylights are known for water leaks and leaking seals. Careful inspection of flashing is very important when inspecting skylights. Some people have been known to caulk over required drainage holes on some skylights. Ensure anyone working on your skylight has a great deal of knowledge and experience prior to letting them repair one.

Rotted Door Jamb

Lack of paint and caulking has caused this wood door jamb to rot. Jamb may be able to be patched and sealed for years of future use but doing simple maintenance would have prevented any damage to door. When ever a painted exterior surface shows signs of paint cracking or peeling it is time to sand of any loose paint and make surface level before applying a sealer and then finish coat of paint.

Rusty Door Skin

Exterior metal door has been allowed to rust and will now require a new door to be installed. This rust may have started from a scratch or dent which broke the paint finish on door. Regular inspection of the exterior of your home would identify any problem areas that require maintenance. A little sanding and painting would have saved homeowner both time and money.

Exterior Check List

  • Visually inspect the exterior of the house to ensure walls are visually plumb and level.
  • Visually inspect the exterior to ensure siding is properly attached to the structure.
  • Inspection of areas where siding or masonry surfaces are missing.
  • Visually inspect the exterior of areas where there is moisture penetration potential due to splits, warping or separations.
  • Visually inspect the exterior of painted surfaces for signs of mold, peeling or cracking.
  • Visually inspect the exterior of the exterior masonry systems and mortar joints to ensure that they are in good condition. Ensure weep holes are present and not below grade.
  • Visually inspect the exterior of masonry surfaces for diagonal cracks with material break through, instead of following the mortar joints. Observe potential differential movement, such as sheering or bowing.
  • Visually inspect the exterior of the window and door lentils to ensure sufficient bearing on the sides. They should not exhibit cracking caused by expanding steel.
  • Visually inspect the exterior for cracks or separations allowing water to penetrate and enter the wood substrate.
  • Visually inspect the exterior of all exterior surfaces for off-color patches, suggesting moisture penetration.
  • Visually inspect the exterior of all the doors and windows for operation. Do the doors and windows open, close, and lock satisfactorily?
  • Visually inspect the exterior of all exterior window and door areas for weather stripping.
  • Visually inspect the exterior of all windows for loose fitting, drafty conditions or broken glass.
  • Visually inspect the exterior of the windows for replacement or immediate repair.
  • Visually inspect all caulking around doors and windows for missing or cracked caulking. Replace as required.
  • Visually inspect any brick or concrete window sills to ensure that there are no mortar cracks for moisture to enter.
  • Visually inspect your asphalt and garage floor joint.  Use asphalt caulking to seal any cracks.

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Window Defects

  • Broken glass
  • Glazing - Glazing compound is the putty-like material that is used to secure panes of window glass in place. Older windows that exhibit deferred maintenance (neglect) should be inspected carefully. Scraping, cleaning and re-glazing can cost as much as painting the window. Of course, this will depend on the condition of the glazing.
  • Broken sash cords - An examination of older wood, double-hung windows should be made for broken sash cords. The newer double-hung windows usually have either a spring device or a small, nylon cord, such as appears in Anderson windows.
  • Malfunctioning window crank mechanisms - These mechanisms are located in casement, awning, and jalousie windows. The hardware for some older windows may not be available, or if it is available, may be difficult to locate. These windows should be checked to ensure that they operate properly.
  • Painted shut or painted open windows - Quite often, windows in older houses are painted shut or painted open.
  • Failed thermal seals - Failed insulated glass seals will allow condensation to form between the two panes of glass. Sometimes, you can see the actual condensation, or other times you can only see the residue. In the early stages of failure, it may be difficult, if not impossible, to see evidence of the failure. The location of the sun, glare, reflections, time of day, angle and whether you are looking from the inside or outside may impact the visibility of stains from failed seals. Significant staining is easy to recognize, whereas early failures and modest staining may not be easy to see.
  • Deteriorated or missing weather stripping - This should be checked, particularly on wood and aluminum windows. Older steel casement windows quite often do not have weather stripping, and there is not a way of easily correcting this situation, short of replacement.
  • Condensation - Condensation may form on the inside of glass or metal frame windows when the relative humidity inside the house is high and temperature difference between the inside and outside is large enough to cause the moisture vapors to change to liquid on the colder surfaces. Look for water or water stains on the stool or windowsill, or at the drywall adjacent to the windows