GBlist: GBList: Re: Dust Mites

Gregory Thomas (
Fri, 28 Feb 1997 16:59:25 -0500

Loren wrote:
> However in most homes which are
relatively leaky, i.e., .3-.7 CFM psf/hr or more, one must augment
this RH through some additional humidification. This is even more
of a problem for homes with forced air heat than for those with
radiant hot water or steam heat.
--- end of quoted material ---

It is the duct leakage and air leakage caused by supply and return pressure
imbalances that cause increased air change rates in forced air houses. Two
buildings could have the same blower door equivalent leakage areas, but
different actual leakage rates due to the driving forces of the HVAC
equipment, if the ducts leak and/or there are pressure imbalances. Forced
air systems don't dry air except through leakage.

Greg Thomas
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