Attic Insulation and Ventilation Balance
Attic Insulation and Ventilation Balance
Proper attic insulation and ventilation is vital to ensure a home is energy-efficient. An improperly ventilated attic can trap heat during the summer, forcing your air conditioner to work harder – increasing your energy bills. In addition, moisture can build up in an unventilated attic and damage insulation and wooden frames if not properly cleaned or insulated.
Most homes have some form of passive or mechanical ventilation. In the former, outside air enters the attic through soffit or eave vents and rises to vents located in or near the top of the attic space. In order for the ventilation system to be effective, approximately equal amounts of intake and exhaust vents should be positioned at soffit or eave level and near the top of the attic space.
For the latter, a power vent or other mechanical device is used to generate air movement, and air is drawn from the bottom of the attic through an open soffit. It is important that the amount of air that is pulled through the attic from the exhaust vents is balanced by the amount of intake air from the soffit and other intake vents, otherwise negative pressure may occur in the attic.
A Homeowner’s Guide: How to Check Insulation Levels Properly
The Uniform Building Code requires a certain number of square feet of attic floor space be provided with adequate ventilation to ensure the removal of moisture and control temperature regulation. This is accomplished through a variety of attic ventilation systems, including ridge vents, gable vents and soffit vents. The size and location of these vents can affect attic air flow, however. In this article, a Computational Fluid Dynamics model is developed to study the effect of baffle size and vent position on attic space temperature distributions and ventilation patterns. The results show that a large baffle size significantly affects the attic space temperature and velocity distribution and that the ventilation ratio is primarily affected by the upper side vent position.
316 Insulation of Tacoma
3010 N 27th St Tacoma WA 98407
253-201-2962