A Little Heat
by Harris Hyman, P. E.
It's been a good year. We've all been busy
designing and building some good houses.
Now it's winter. How do we heat them?
In 1970, a quality, energy-efficient house
consumed about 11 Btu per square foot per
degree day (DDay), but today we'd be foolish
to be satisfied with a house that used more than
2 Btu.
The state of Maine has voluntary standards
of about 4.7. A few of us work in the area of 1
(and solar engineer and inventor Norm
Saunders has more than a casual acquaintance
with 0.0), but most reasonable builders aim for
between 2 and 3.
Assuming our 1970 house had 2,000