courtney (01/09/83)
#R:dvlcn:-9300:hp-pcd:5000008:000:2292
hp-pcd!courtney Jan 8 17:55:00 1983
In response to the initial premise of Dave's posting
"As you ALL know...", a couple of comments:
*** "Energy efficient houses" do not have a chimney. ***
If they have the facility to burn wood, they do so
with a wood-burning stove which uses a flue and gets
its combustion air from outside (though a small duct).
*** Even in very well-built houses (ie., built with
energy efficiency in mind), up to half of all heat
energy loss is due to infiltration (air leakage
through walls, around doors and windows, etc.). ***
In less well-built or older homes, the energy loss
due to infiltration can exceed 70% of the energy
budget of the house. Consideration of this reality
leads to construction ideas such as the following:
-build the home with a plastic lining between the
insulation and the interior siding of all walls,
ceilings, and floors (the vapor barrier must be
on the INTERIOR SIDE of the insulation to avoid
moisture problems, in agreement with the fact
that moisture is flowing from the inside of the
building to the outside).
-to the greatest degree possible, locate all
plumbing and wiring (including sockets and
switches) in interior partitions, rather than
walls which share a side with the great outdoors.
This minimizes interference with the insulation
and vapor barrier which reside in these exterior
walls.
-now that a building has been created which is
completely unlivable due to domestic pollutants
and the lack of fresh air (if there is any of that
outside), one or more (passive) air-to-air heat
exchangers are installed at appropriate locations
in the building to provide ventilation while
recovering upwards of 70% of the thermal energy
in the exhausted air!
(By the way, an "adequate" ventilation rate for a
room with people smoking is about 10 times that
which is considered adequate for rooms without
people smoking...)
*** As to doing better with radiant energy lost from
windows, I have not seen a system which does not
have any of the drawbacks that Dave listed. ***
Courtney Loomis