Frequently Asked Questions

How do Window contractors windows rate compared to other windows?
Our windows are rated among the finest available -- check the ratings by the major consumer magazines. Among vinyl windows, Window contractors is the number one choice of remodeling contractors and builders all across the nation. For more than a decade, ours have been the vinyl window more professionals recommend, according to studies by the major trade magazines. And they've been chosen for more than three quarters of a million homes -- that's more than 15 million windows -- so they've proved themselves for the long haul in every kind of environment.

How much do Window contractors Windows cost?
Because Window contractors only sells window products directly to building supply distributors and dealers, it is their customers -- the window installers, home remodelers and general contractors -- who determine consumer prices. Use our "Locate a Contractor" for a listing of contractors you can contact for pricing information in your area.

How can I be sure the window installer, remodeler or contractor is qualified to install Window contractors window products in my new or existing home?
It is always a good practice to ask your window installer, remodeler or contractor for local references, you can also call your local Better Business Bureau and call the local Builder's Association in your area. Ask who their building materials distributor is and contact that building materials distributor for additional information.

What is the "R-Value" of Window contractors windows?
You've probably heard of the "R-Value" rating used in relation to insulation products. But "U-Value" is the tool the window industry uses in the objective ratings comparisons established by the National Fenestration Ratings Council. U-Value measures the rate of heat flow through a glazing system -- the lower the U-Value, the better the insulating quality of the window. Center of the glass U-Values measure the performance of the glass system. Total unit U-Values measure the performance of the entire window, taking into account frame, sash, airspace, the spacer between the panes, as well as the glass.

U-Value can be compared to R-Value - which is the resistance of a material to heat flow -- by dividing 1 by the U-Value. (Thus, a U-Value of 0.5 equals an R-Value of 2.)

Window contractors has developed Thermaflect®, a proprietary glazing system with a unique, two-layer, low emissive (Low "E") coating on the glass. It selects the most beneficial wavelengths of light and heat to let through, and reflects the others away. It balances the transmission of visible light and heat for excellent performance in keeping your home warm in cool weather and cool in warm weather, helping you save on energy year round. It does this while reducing the amount of damaging ultraviolet light entering your home by 84%. And Thermaflect does all this without distorting the view.

A total system of Thermaflect glass, argon gas (which insulates better than air), and a low-conductance spacer (which reduces conductivity of cold through the glass) ensures excellent thermal performance.

What is condensation, and what can I do about it?
Condensation occurs when humid air comes in contact with a surface that is cooler than the air itself. In winter, when your high-quality vinyl windows are efficiently keeping cold air out and warm moist air in, condensation may appear as fog or moisture on the glass.

Condensation does not indicate a problem with your windows; quite the contrary. It means you're holding in warm air like never before. But you're holding in humidity, too. That's the problem.

You create humidity every time you cook, shower, clean, or merely breathe inside your home. Other contributors to household humidity are humidifiers, water pans on radiators or wood stoves, kerosene heaters, drying laundry, and house plants.

The basic rules of thumb says that at 20 to 40 degrees outside and 70 degrees inside, the humidity in your home must be below 40% to avoid condensation. At 10 to 20 outside, your humidity must be below 35%.

Here's what you can do to reduce the humidity that causes condensation:

• When using your bathrooms, kitchen or laundry room, turn on any built in fans. It is also a good idea to install an exhaust fan in your attic.
• Use a dehumidifier to remove excess moisture from the air.
• Every day, open a door or window briefly to air out your home. Opening fireplace dampers and basement or attic louvers will also work.
• In cold weather, move your house plants to a seldom-used room.
• Waterproof your basement floors and walls with moisture-sealing paint.

What is a low-conductance spacer, and what is it made of?
A low-conductance spacer is an integral part of CertainTeed’s Thermaflect® Low "E" glazing system, helping the system to deliver the best R-value rating in its class. The low-conductance spacer is a new technology, an improved design of the strip of material that has been used for many years to separate the panes of glass in a multi-pane window.

The original spacer material in the window industry was metal -- usually aluminum. Unfortunately, these spacers conduct heat very well, so the edges of the glass would lose more heat than the center of the glass. This inequality of temperature often caused condensation to form on the inside of the window, and could actually lead to stress fractures in one or both glass panes.

Low-conductance spacers are specially designed to enhance thermal performance. They reduce the conduction of heat from a window’s interior pane to its exterior pane, resulting in an inside pane temperature up to 9 degrees warmer than the outside pane. That means low-conductance spacers create a more uniform interior glass temperature, which significantly reduces condensation as well as the chances of stress fractures in a pane of glass.

CertainTeed uses low-conductance spacer systems that are manufactured from a variety of materials, including butyl, stainless steel, and structural foam. In every case, the overall performance of these systems is comparable.

Can I paint or stain my windows?
One of the benefits of vinyl windows is never needing to strip, paint or stain them. Painting your vinyl windows can void your warranty.

Is there condensation on my windows?
Condensation on interior surfaces of windows and doors occurs because of high humidity and insufficient air exchange inside the home. In many older homes there were gaps in the windows where drafts could be felt and air would flow. This exchange of air, in many cases, was sufficient enough to prevent condensation from forming. The high-performance windows of today are designed to be air tight to reduce heat loss. This reduces air flow windows. Again, this is not a window defect.

Condensation on exterior surfaces of windows and doors occurs because of the increased efficiencies in today's windows. On clear nights with still, humid air, condensation occurs when moisture-laden air comes in contact with a glass surface that is below the dew-point temperature ("dew-point" is the temperature at which the air will no longer hold its' moisture vapor. Cold air holds less moisture vapor than warm air). In high-performance windows with LoE and argon gas, the outside glass surface will actually be colder than a similar, "regular" window without these features. This is because the high-performance window is reducing heat flow to the outside and preventing the warming of the exterior surface above dew-point. This is not a window defect; like dew forming on grass and car-hoods, it is a natural phenomena.

Other factors that influence condensation are:

• Window Size - Larger windows may have a higher tendency to show condensation.
• Window Location - Windows protected from the wind will have a higher tendency to show condensation.
• Screens - Windows protected by exterior screens may have different condensation than the same windows without screens under the same conditions.
• Air Circulation - Good air circulation, such as exposure to wind, reduces the occurrence of condensation. Building projections, foliage and other wind-breaks may contribute to condensation.
• Interior Shades - Opening interior shades or blinds may reduce condensation by allowing more heat to transfer to the outside.
• Minor differences in conditions can cause condensation to form on one window and not on another -- even when they are side-by-side.
• Finally, condensation on windows can be a seasonal or a night-time event. When outside temperatures are warm, the glass temperature will usually be above dew-point.
• The same is true during cold, winter weather. Condensation will most often occur during transition months.

Why is it not recommended to have darkly tinted and LoE glass in my insulating glass unit?
It has been shown through Insulate's own experience that this combination may cause a seal failure in the insulating glass units. We believe this occurs because tinted glass tends to trap heat inside the home, whereas LoE tries to reflect outside heat back out. Both working together causes heat to build up between the two panes of glass, resulting in seal stress, and eventually unit failure.

Why isn't my garden window NFRC rated?
Presently, testing methods for garden windows have not been developed