Watch out for Air Quality

Thanks to state-mandated requirements, today’s homes are being sealed tighter
and tighter. With less air getting in and out, how is air quality being affected?
Three years ago, Massachusetts passed the “stretch energy code,” which
gives municipalities the option of adopting energy-effi ciency requirements that
exceed those in the Commonwealth’s “base” building code. These standards call for
improved energy effi ciency in new construction and major remodeling of residential
and commercial buildings.
One of the primary ways builders and remodelers are meeting these requirements is
the use of improved insulation. As we mention in this issue’s cover story, closed-cell
spray foam — the gold standard for insulation — has become increasingly popular.
Spray foam does its job so well that it’s having an impact on air exchange.

What Is Air Exchange Rate?
What Is Air Exchange Rate?

The Environmental Protection Agency
defines “air exchange rate” as “the rate
at which outdoor air replaces indoor air.”
A lack of air exchange can trap stale air
and moisture indoors, which can really
be a problem in basements. And with
excessive moisture can come molds,
various other allergens or even dangerous
gases like carbon monoxide.
So if you have an energy efficient home, you have to be mindful of air exchange — especially in the basement.
One solution we like is the Lifebreath system ( This
mechanical ventilator has two ducts — one that sucks in fresh air from outside and
another that expels stale air from inside. (Some air conditioning units perform a
similar function.) The manufacturer also claims the system produces savings on
heating and cooling.
Another solution to consider is the Humidex ( This moisture
control and ventilation unit expels humid, contaminated air, which is then replaced
by dry, fresher air coming from the upper levels of the home.
If you need advice on purchasing systems like these for your basement or elsewhere,
please call Custom at 781-648-2835.



Custom Contracting, Inc. 1267A Massachusetts Ave. Arlington, MA 02476 Phone: 781-648-2835 Fax: 781-648-0907 Email:

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