GBlist: RE: Winter Ventilation 2

[Charlotte Matthews <Cmatthews@payette.com>]

Steve & folks,

I'm afraid its all hypothetical at this point.  The house has not yet been
winterized and the addition is yet to be built.  My systems research is all
part of the design.  The specs will be written with all the right language
and requests to construct a tight house, but I'm skeptical that a house can
truly be winterized "air tight".

The house will not be heated with forced air if I can use passive vents.  I
had planned on using radiant heating panels upstairs and radiant flooring on
the bottom floor, fed by an/multiple instantaneous water heater(s).  That is
why this issue of winter ventilation is so big.  If we need to install
ductwork for ventilation, we might as well go to a forced air system with
heat recovery, I figure, and make the whole issue of a separate ventilation
system moot. 

I am looking at ventilation only because I've read so many warnings against
making a house tight and then not providing for ventilation.  I've also
heard that its better to insulate a house tightly and provide mechanical
ventilation than to allow the place to breathe and ventilate naturally.  In
answer to your last question, I intend to provide winter ventilation because
I think it is the "right thing to do". There are no existing problems with
moisture.

I wanted to go radiant, so that energy would not be expended to heat
portions of the house that are unoccupied.  Perhaps I am wrong in thinking
that forced air is really a total house system???

Hope that this gives you the extra few clues you need-

Thanks for your consideration,
Charlotte

 -----Original Message-----
From: Steve McCarthy [mailto:smccarth@pct.edu]
Sent: Tuesday, November 21, 2000 12:05 PM
To: Cmatthews@payette.com
Subject: Re: GBlist: GBList: Winter Ventilation


Hi Charlotte,
Some additional info might be helpful for the folks that are
considering your ventilation questions.
1. How tight is this house? What is the CFM50 or ACH50? To say that it
was winterized or that the addition was built to be tight offers no
concrete info on how it actually performs.
2. Is the house heated with forced air?  An operating forced air system
almost always causes the natural air exchange rate to increase whenever
the fan kicks on. Forced air systems also mix the air in the house and
offer some options for low cost ventilation.
3. Does the house need ventilation because there are existing air
quality problems or because of a moisture load that is NOT related to
occupancy?
4. Will the unused  portions of the house be heated when not occupied?
5. Do you want to ventilate this house because it's the "right thing to
do" ? Have the occupants complained of a problem or have you noticed a
problem?

Steve McCarthy/ Starbright Energy Services


5. 
______________________________________________________________________
This greenbuilding dialogue is sponsored by CREST <www.crest.org>
BuildingGreen <www.buildinggreen.com> and Oikos <www.oikos.com>
For  instructions send  e-mail to  greenbuilding-request@crest.org.
______________________________________________________________________