Air Leakage

Here at The Window Man we pride ourselves on being the Educational Window Company. We start the educational process by talking about the three Window Evils.

1 Air Infiltration 60%
2 Radiant Heat 30%
2 Conduction/Convection 10%

Today we're going to talk about air infiltration, also called or air leakage.

Air leakage is unwanted amounts of outside air entering the house through cracks and small openings. A leaky house allows moisture, dust and allergens into your home, making it unhealthy. As air pressure changes in your home, these same leaks also allow heated or cooled air to escape. These air leaks waste energy dollars! Air infiltration causes cold drafts and temperature differences within a room, which frequently causes the thermostat to be set higher or lower, so that the average temperature is at the desired level. The Window Man takes pride in only selling windows that far exceed industry standards to reduce the air infiltration into your home.

Air leakage may come from gaps and cracks around the windows and doors in your home and can account for 50% of your heating costs. By reducing air infiltration, you can use lower thermostat settings and your comfort level significantly increases.

A good analogy is to think of going outside on a cold, windy day wearing an expensive, good quality winter coat all decked out with thermal fleece and water repellent, but if you don’t zip it up, you get little of the benefits you paid for.

Choose a window that has been tested and AAMA certified for air infiltration. If a manufacturer elects to have its product tested, it cannot have more than 0.3 cfm/ft2 of air leakage per linear foot of crack space.

Vinyl is the most popular material windows are made from, but vinyl moves! Vinyl expands and contracts 10 times more then other window materials and windows are tested at normal room temperatures. Our experience shows that vinyl windows need to be tested at “.10” cfm or less, which is 3 times better than a passing grade so they don’t become drafty in the winter when they shrink.

U and R Values Explained

Customers at The Window Man's three Northern Virginia locations are often confused about (U) and (R) values and how they rate a window's insulation capabilities.

One way that insulation is created is with dead-air space between panes of glass. Therefore a double-paned window gives more insulation than a single-paned one. Other factors contribute to the insulation qualities of a window, such as the gasket, the material type, and the gas used in a gas-filled window. The U/R value tells how the product insulates. It is a formula derived from the efficiency of the product, and that formula takes into account many of the factors just mentioned. A good R measurement is a high one, while a good U measurement is low since U is the reciprocal of the R. Homeowners are more interested in the R value, while builders are interested in the U value.

As you're looking for new or replacement windows, you're probably wondering what some of the pros and cons are of each of the different types of windows materials. Take a look at The Window Man's website for a full list, but here's a breakdown of clad wood's pros and cons.

Pros of Clad wood

• Low Exterior Maintenance
• Color Choices
• Interior paintable/stainable
• The look and feel of real wood
• Hardware Choices

Cons of Clad wood

• Cost
• Lack of exterior detail
• Interior maintenance
• Quality can vary

For more information please stop by one of our three Northern Virginia showrooms. We'd be happy to talk with you about the different window materials available to you.