Crawlspace question

[Doug Kanter]

Note: This is NOT a question about how to insulate the crawlspace mentioned below. I already know what needs to be done there in the spring when I rip out the floor.

Onward:

45 yr old ranch. The whole thing's over a full basement except for a 10x8 part of the kitchen that's over a crawlspace. Who knows why - maybe it made the house cheaper to not extend the basement. Anyway, the only openings to the crawlspace are two 8" x 24" rectangular cutouts in the wood supporting the house. Just small enough to be useless. But, they're open to the basement and cold air's pouring in.

Bought the place last September. It's well maintained, except I keep finding little things that make me wonder why nobody dealt with them before. For instance, there's no fiberglass batting stuck up between the rafters at edges of the basement. What I'm wondering, though, is if there's a good reason for those crawlspace gaps to be left open. Maybe to prevent moisture buildup in the space? Peering in with a flashlight, I can see that there's no plastic over the bare earth, no insulation of any kind (which is why I'll be attacking it in the spring).

I'm not trying to heat the basement, but it can't be good for the house in general to have that cold air coming in from the crawlspace. Any reason to leave them open?

[Matt]

Hmmmmmmm

If you seal it up, then the decay from all the dead bodies buried by the previous owner will become too obvious?

[Doug Kanter]

Possible, but I wonder why he'd do that? The house is 30 seconds from a large body of water. :-)

[George E. Cawthon]

If you aren't worried about freezing pipes (not that cold) in the crawlspace this winter, I tape plastic over the holes. Then get it fixed in the summer. Sounds like this is an opportunity to extend the basement, depending on how the house above the crawl space is supported.

[Ron]

I think you got it right, you need air circulation in the space to reduce moisture. Ron

[Mark]

put a vapor barrier plastic sheets down over the bare earth and add some ventilation in the crawl space to the outside, then seal it from the rest of the basement (in a way that you can open it for service access).

Mark

[Doug Kanter]

That's what I'm going to do in the spring, but I can't access it through the small holes. The entire kitchen floor is in bad shape (some sort of linoleum). So, my plan is to rip it out, and in the 1/3 of the room that's over the crawlspace, take out the floorboards, too, giving me total access to the bare earth.

There are no pipes in or near the crawlspace area. I want to believe (?) I'm not risking much if I close the two access holes for 3-4 months.

[George E. Cawthon]

You're not risking anything. The standard procedure for crawl spaces in cold areas is to close the foundation vents in the winter. And they make vent closures that are not only tight, but insulated as well. If the walls around that craw space are tight, I'm not sure why you have cold air pouring through the two slots to the basement. Nonetheless, closing off those two slots to reduce air movement would likely make the crawl space warmer. Moisture in the crawl space is not normally a problem in winter.

[Doug Kanter]

Because the slots are open and cold air sinks. I guess "pouring" was the wrong word. One crawlspace wall faces the garage. One faces the porch, and is not visible from outside - the cement porch covers the cinder block completely. The one that's exposed faces the back of the house, and appears to be well sealed. So, air's not really leaking in, but it *is* much colder in there, and cold air wants to move somewhere.

[Doug Kanter]

Ever have a "duh moment"? I was just in the basement and noticed that the cutouts to the crawlspace are exactly the size of the rectangular heat ducts in the rest of the cellar, plus about a quarter inch of wiggle room in all dimensions. No ducts in the holes, though. Talk about choosing options badly. I wonder what the original owners were thinking?