Window replacement evaluations and ratings
Not surprisingly, wood and fiberglass clad window frames have the highest rating. (These replacement windows have the highest prices, too.) These window frame materials are best at keeping out rain, wind, and the elements. Each window was subjected to a week of extreme temperatures to see how the window expanded, contracted and flexed with changes in temperature and condition. Each window was then tested for water and air leaks. Windows that showed little to no change in performance from start to finish were ranked higher.
Vinyl is less expensive and convenient
Vinyl replacement windows account for nearly 50% of the market because they are reasonably priced and require no maintenance. However, vinyl windows will let some air through, especially in colder climates. Additionally, vinyl is less attractive than wood siding and cannot be stained or painted to match or complement a home’s exterior color ESWDA.
Replacement window classifications
When comparing the same type and style of window from different manufacturers or even different lines from the same manufacturer, you’ve probably noticed one thing: no two windows are exactly the same. Do not panic! You don’t need to resort to anything as drastic as defenestration or jumping out of a window. To ensure that your replacement windows provide you with great home comfort and energy cost savings, the National Fenestration Rating Council or NFRC and Energy Star provide a useful rating system for evaluating the quality of windows and energy efficiency.
It can be difficult to compare the claims made by different window manufacturers, mainly because they often use different window measurements and rating terms to sell their products. For example, some may use the R-value of the center of the glass and the shading coefficient, while others use the U-factor of the entire window and the solar heat gain coefficient. Fortunately, now there is one place to look that has standardized ratings for Windows: NFRC. The National Fenestration Rating Council (NFRC) is a nonprofit coalition of window manufacturers and experts that has established standards for testing and labeling windows.
The National Fenestration Replacement Council
The NFRC has developed a fairly comprehensive window performance / energy star rating in which they provide uniform and definitive benchmarks by which all window companies must now measure the energy performance of a window. You can easily compare windows from different manufacturers or different lines from the same manufacturer because the information is conveniently and accurately presented in an easy-to-understand summary. However, you should be aware that windows are evaluated and rated when new and therefore long-term strength is not taken into account. In addition, the City Council does not carry out studies on the windows already installed or their history.
The NFRC Window Replacement Rating System
The key element of the National Fenestration Replacement Council’s rating system is the U-factor of a window. The NFRC gives each window a U-factor rating. The first number after the words U-factor is the appropriate rating for residential purposes. It will be marked AA or Residential. The U-factor marked BB or Non-Residential is for commercial window applications. The U factor on the NFRC label always refers to the entire window. To make sure you are comparing apples to apples, ask for the NFRC ratings even when there is no label on your window replacement. Also, be sure to use windows of the same size for comparison, as the glass-to-frame ratio affects the result.
The U-value measures how much heat actually flows through a material. NFRC has U-value measurements of different replacement window systems. Simply put, the lower the U-value, the greater a window’s resistance to heat flow and the better its insulating value. The U-factor rating ranges from 0.10 to 1.20. The lower the U-value, the lower the heating costs. You can also compare air leaks. This rating corresponds to the ratio of the number of cubic feet of air that passes through a window divided by the square feet of window area. The lower the AL, the smaller the leak.
Another factor to consider is the solar heat gain coefficient (SHGC), which measures how well a product blocks heat caused by sunlight. SHGC is the