Reducing Heat Loss and Condensation

Reducing heat loss through your windows is how homeowners save big money!  But you have to know what to look for in order to purchase the window that does the job right. Manufacturers usually characterize the energy efficiency of windows in terms of their U-values or their R-values.  If you are looking to purchase quality replacement windows that will lower your heating and cooling costs, make sure to learn about U and R-values. 

U-value: Conductance of heat. U-values range from 1.1 to 0.3.

R-value: Resistance to heat flow. Usually, window R-values range from 0.9 to 3.0.

When a window's R-value is high, it will lose less heat compared to one with a lower R-value. On the other hand, if a window's U-value is low, it will lose less heat than one with a higher U-value. Basically, U-values are the reciprocals of R-values (U-value = 1/R-value). But when it comes to purchasing new replacement windows, it is important to know that most window manufacturers use R-values in rating their windows.

Above we have mentioned the typical range for U-values and R-values, but keep in mind that some highly energy-efficient exceptions also exist. When comparing different types of windows, you should make certain that all U-or R-values listed by manufacturers:  

• Are based on up-to-date standards put in place by the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE).
• Are calculated for the window in its entirety, not just the frame and not just for the center of the glass. Everything must be included. 
• Represent the same size and style of window.

Below we have listed the 5 factors that affect the R-value of a window:

• The type of glazing material.  Whether its glass, plastic, treated glass, etc.
• The number of layers of glass. Single, Double, or Triple?
• The size of the air space between the layers of glass. 
• The thermal performance of the frame and spacer materials.
• The tightness of the installation.  This refers to air leaks, drafts, etc. 

Interested in More Information About Replacement Windows?

Replacement windows can save you a ton of money which is why they are a great investment. However, you will want to make sure you are choosing the right replacement windows for your home and your budget. Our services can help you! We offer Free Replacement Window Quotes from reliable local contractors.