I live in northern Westchester County, N.Y. My house is built above a
crawl space with a dirt floor. Last year I had expanding foam
insulation installed between the floor joists above the dirt floor. The
height between the dirt floor and the bottom of the floor joists varies
from a high of about five feet to a low of about six inches (the house
is built on a slope).
I have heard conflisting theories about ventilating a crawl space. One
theory says keep vents open in winter and closed in summer. That seems
counter-intuitive to me.
At one end of the house I have a window opening to the crawl space
measuring about three feet by three feet. In spring, summer and fall I
place a screen in the opening. During winter a place a solid door in
At the other end of the house there is a small window (27 x 17). In
spring summer and fall it is covered by a screen. In winter by a solid
Here's my question.
Should I cover the two aforementioned windows with the screen, or solid
covering, in the spring, summer, and fall? What about winter?
Is it necessary to cover the dirt floor with polyurethane?