R-5 windows is a relatively new program issued by the US Department of Energy. Its main goal is to encourage the US homeowners including those living in Connecticut to buy high performance replacement windows rated at least R-5. Window replacement ct This goal is to be achieved by giving the manufacturers different kinds of incentives that will lower the price for the final consumer. R-Factor or sometimes called R-Value is simply a reciprocal of the U-Factor. Therefore, in order for the window to be rated R-5, its U factor must be at least .20 or less. In comparison, majority of the windows (Energy Star) rated have U-Factor of about .28 or .30, which means that their R-Factor is around 3 or 3.33. R-5 value is huge improvement over the current R-3 required for Energy Star. It is pretty common knowledge that when you replace your windows, it may be one of the wisest investments you have ever made in your home. Window replacement ct So when the time comes for your windows to be replaced, it just makes more sense to realize a quicker return on investment by saving more on your utility bill.