Insulation recommendations are based on certain factors that coordinate with regional climate zones to increase energy efficiency. These factors are known as R-values. The R in R-value stands for “resistance,” and refers to how certain products resist the flow of heat through walls, floors and ceilings. Products should reduce heat escape so heat is kept on the right side of the wall. In summer this means outdoors, in winter it means indoors. R-values relate not only to insulation, but also to walls, windows and other barriers. R-values also coordinate to the type, thickness and density of the material being used. The higher the R-value, the more resistant to heat the product is. The U.S. Department of Energy coordinates R-value to climate zones 1 through 7 (1: Tip of Florida; 7: Canadian border). A higher R-value is needed in Zone 7 and a lower R-value is necessary in Zone 1. Those embarking on home improvement projects that involve choosing between R-values are urged to speak with a professional or to visit the Department of Energy website (www.energy.gov) to determine which R-Value is ideal for their homes.