An energy efficient home will perform optimally as an integrated system for maximum comfort, efficiency and durability. Looking at a house as a system is the only way to ensure that insulation, air tightness, and ventilation will work together to make a successful energy efficient house.
The insulated shell of a house is referred to as the building envelope. The building envelope includes the exterior wall spaces, ceiling and the floor. Heat moves through buildings by transmission and air leakage. Insulation works to slow the movement of heat through the building envelope. Different types of insulation function differently to cut down on heat flow. The effectiveness of insulation is measured as "R-Value" where "R" refers to resistance to heat flow. The most effective forms of insulation have the highest "R-Value".
Air tightness is the other main concern for building envelopes. Air leakage, or infiltration, is one of the biggest sources of energy loss in most buildings and accounts for about a third of heat loss in most typical homes. All the leaks taken together can amount to a hole about the size of an open window, so it deserves considerable attention. Air leaking through the building envelope causes unwanted heat loss in the winter and heat gain in the summer. Although fresh air is needed in any house to be comfortable, it is important to control when, where and how much fresh air comes in. Second, by keeping air from moving through the envelope, moisture is kept out of wall and ceiling cavities where it can reduce the effectiveness of the insulation and even cause structural damage.
Home Energy, Inc. has mastered the building envelope through the use of three highly efficient soluions:
