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The Efficient Attic Solution
The four step approach outlined below considers the whole attic as a system. Addressing all forms of heat gain/loss and moisture related concerns is essential to creating an efficient, healthy, cost effective, and sustainable attic system.
STEP 1: Install Radiant Barrier Under the Roof
Radiant heat is typically the single largest source of heat gained by a building in the summer. According to the Department of Energy, installing radiant barrier can reduce cooling bills by up to 17%.
STEP 2: Ensure Adequate Attic Ventilation
Proper ventilation is essential to control moisture and heat buildup in an attic space. Most attics are extremely under ventilated making them vulnerable to moisture related problems and excessive heat build up. A correctly sized solar exhaust fan coupled with adequate soffit venting ensures proper attic ventilation.
STEP 3: Air Seal the Ceiling
This vitally important step is completely ignored by most builders and insulation contractors. Air infiltration typically accounts for 40% of the heat lost by a building in the winter. The attic floor (ceiling) is generally the most leaky assembly in a home accounting for a large percentage of air leakage. Air leaks through all the many penetrations including: recessed lights, speakers, wire penetrations, plumbing penetrations, flue pipes, air ducts registers, attic hatches, top plates and more.
STEP 4: Air Seal and Insulate Duct Work
Typical duct systems leak up to 30% of their air. Some of the air that you just paid to heat or cool leaks out of the system before even entering the living space. The overall efficiency of the HVAC system is reduced by the amount equal to the duct leakage.