At Dependable Construction we understand that your home improvement dollars are limited and that your priority as a homeowner is to always make sure you get what you expect when you pull out your wallet. So its best that homeowners understand exactly what their getting when considering purchasing new replacement windows.

New windows, as I’m sure you know, are much more than two ordinary pieces of glass held together in a frame. Windows have evolved even over the past few years as research and development have delivered more efficient products to the marketplace. Window glass today is actually quite high tech so they do a lot more than provide a nice windbreak and view through.

Along with the advanced technology of today’s replacement windows has come industry standards and measurement rating to guide homeowners in their replacement window selection.

Window ratings.

When it’s time for new windows, it can be very tempting to believe everything you hear from one of the so call “experts” that show up at your door. Dependable Construction however has been a longtime trusted window contractor in Dayton, Oh. We understand that the bes advertising a company can have is positive word-of-mouth. That’s why we always first explain to homeowners who are looking at replacing their old, inefficient windows the U Factor and other ratings for energy efficiency that they will encounter while shopping around.

U Factor ratings were developed by the National Fenestration Ratings Council (NFRC) as a way to measure a window’s energy efficiency, using four different criteria. Fenestration, by the way, is just a fancy name for windows. All windows are given a rating between 1 and 3, with the lower numbers being representing better efficiency, to make it is easy for consumers to make meaningful comparisons between their replacement window choices.

You may be familiar with the U.S. government’s Energy Star ratings from the last time you purchased a new refrigerator or washer and dryer. In the window industry, the only windows that meet the standard for an Energy Star efficiency rating are those that also meet NFRC standards for energy savings.

Just like the appliance industry has made improvements in the efficiency of their products, the replacement window industry has made remarkable progress in building products that can help to decrease the amount of energy it takes to heat and cool your home.

But not all replacement window contractors offer the same quality of window, which is why it is important to understand the ratings before making a decision on replacement windows that a homeowner will most likely have to live with for many years to come.

Many contractors will sell thermal replacement windows without ever discussing the U-Factor ratings, but as a consumer you should always ask for these numbers before deciding what you will buy. If a contractor tries to tell you that ratings don’t matter or that all replacement windows are alike, walk away.

While we can all agree that today’s windows are far and away more efficient than the original windows in homes more than a few decades old, all window manufacturers are not created equal. That’s why Dependable Construction uses Siminton Windows as our main source for high-quality, energy efficient windows. The beautiful, functional help add immediate curb appeal to our customer’s homes.

The NFRC ratings are done in the following areas:

U-Factor — Similar to the R-Factor rating on home insulation, the U-Factor, sometimes called a U-Value, measures the amount of non-solar heat loss that occurs through the window. Values for U-Factor range from 0.15 to 1.20. The lower the number the more efficient the window because it has more insulating ability.
Solar Heat Gain Coefficient — Measures the level of “heat gain” during the summer months. Solar radiation that passes through windows is measured in terms of its solar heat-gain coefficient, or SHGC.  SHGC ratings are a useful way to quantify the energy efficiency of windows. Whereas the U-Factor is used to quantify the amount of non-solar heat that passes through a window or skylight, the SHGC quantifies the amount of solar heat that passes through the window. SHGC ratings have a value between 0 and 1, with 1 being the maximum amount of solar heat passes through the window and 0 being the least. An SHGC rating of .30 means that 30 percent of available solar heat is able to pass through the window.

Air Leakage (AL) — This refers to the window assembly and not the glass. The Air Leakage rating is based on the measurement of air that passes through leaks in the window assembly in terms of the number of cubic feet of air that a square foot of window area. A rating of .30 or less is required for a window to achieve an Energy Star rating, so if you don’t see the Energy Star symbol on the windows you are considering as replacements for your old, inefficient windows, you know that they have too high an AL rating.

Condensation Resistance (CR) — A CR rating is a measurement telling us how well a window resists the formation of condensation on the inside surface of the window. CR values from 1 to 100 are based on interior surface temperatures at 30%, 50%, and 70% indoor relative humidity for a given outside air temperature of 0° Fahrenheit under 15 mph wind conditions. Unlike the other energy ratings that apply to windows, a high number is a good thing when it comes to condensation resistance.

Visible Transmittance (VT) — measures the amount of light that can pass through a window, and has less to do with energy efficiency than with homeowner preference (VT) is an optical property indicating the fraction of visible light transmitted through the window. Specially selective coatings on quality modern replacement windows permit different amounts of visible, infrared and ultraviolet light. The higher the VT rating, the more light passes through.

As you can see, a lot goes in to determining whats the best replacement window. As a trusted window contractor in the Dayton, Oh area, Dependable Construction encourages customers to look at all of the relevant NFRC ratings, as each of them play an important role in determining which type of window is best for their home.



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