Question re: crawl space and freezing temps.greenspun.com : LUSENET : TimeBomb 2000 (Y2000) Preparation Forum : One Thread
How long can one assume it will take to dip to freezing in a crawl space of an unheated home at about 15 degrees fahrenheit (space is about 3 feet below surface)
-- OR (email@example.com), December 09, 1999
It's hard to say. In an unheated home, not too long. A lot depends on how welll insulated are the walls of the crawl space and the floor above it.
It also depends on the wind conditions and snow cover.
In calm conditions, a well-insulated space would probably take a couple of weeks to get down to freezing, assuming that it was warm in there to begin with. But this is only a guess.
If you know a heating contractor, he would be able to run a heating load program of your home and get some idea of how fast it would lose heat. That would give you some definite idea.
-- gene (firstname.lastname@example.org), December 09, 1999.
OR, I have carefully assesed the temperature of the crawl space in my own home. Remarkably it mimics the inhouse temperature minus 20 degrees. This assesment was done with various levels of heat in the house.
Gene is correct in pointing out that colds winds are the most damaging condition for a crawl space. Here in montana any air leaks in crawl spaces will eventually lead to frozen pipes. \ In my estimation at 15 degrees with no heat in the house the time in your crawl space before freezing is probably the next day. In any case your best bet is to make some other arrangements.
Someone may correct me but I believe the ground in any area maintains a constant above 40 degree temperature at a depth of 6 feet. Every foot in the ground is a significant improvement from the tempertures at the surface. Also rigid foam (styrafoam) has the best insulating factor of anything you may choose to plug and cover such a hole.
Or, I,m a homebuilder. I have considerable experience with protecting homes from severe weather. If you care to e-mail me with your dilemma I'd be glad to share any relevant experience.
-- Rob Carroll (email@example.com), December 10, 1999.