Air Quality 

"Whole-house ventilation is one of the most important issues in residential energy efficiency."  from Residential Energy by John Krigger

In the past, an old concern was that a building could be "too tight".  This was based upon the concept of letting air leakage provide ventilation for indoor air pollutants.  Because air leakage can vary with the weather (wind and temperature) and is not uniform through out the whole house, this is no longer an acceptable practice.

Building science uses ASHRAE ventilation standards to develop a Building Airflow Standard (BAS).  This is used as a guide with blower door monitoring as work progresses, for both the homeowner and air sealing technicians to observe.

A house can be mechanically vented for air cleaning in three ways.  Exhaust fans in kitchens and baths pull in outside unconditioned air while blowing out polluted but conditioned air.  Supply side whole house fans pull in unconditioned air and push inside air out the leakage areas.  These methods can be acceptable in certain situations, but are not as efficient as a home air cleaner with two fans in a heat exchanger or heat and moisture exchanger.  These heat and energy recovery units actually use outgoing air to "condition" incoming air and have good efficiencies.

Radon mitigation•  We install the ventliation fans designed especially for this serious, but often forgotten health problem.

R. McLagan, Inc., 14 Kings Court, Clifton Park, NY   518-383-2421