a crawl space. The floor joices, etc...had to be replaced from the bathroom to the front of the house. I noticed that the ventilation spaces where all blocked off. Now that I have removed the insulation and blocks to let air circulate, I noticed that the one's in the bedroom have been boarded over with only about 1/4 inch opening and with no screen to keep the critters out. (And they are cominging in, yuck.) It is heated by oil and they have used one the ventilation spaces to run the oil into the house. Of course I don't know what I am doing but I have thought about drilling some holes in the wood and then using cement nails to attach the screen on the outside of the cement block. And then maybe makeing some kind of wood thingy(?) with insulation to lay up against it in the winter. I have also noticed that the addition to the house(it's a very old house) does not have any ventilation space area openings for the crawl space. Any suggestions? Also what is ground gases, how do you detect it and how do you prevent it?
Thanks for the advice. Sorry if I sound a little (more than a little) brain dead, but where should the dehumidifier be placed. In the crawl space? Or inside the house?
The inspector told me to put the dehumidifier in the crawl space. Keep in mind this is only if you close off the entire crawl space. By closing off I mean building a woody thing to put in the window wells. Or you could but foam insulation (about 1" thick) and cut it to size.
If you go the dehum route the object is to keep all the outside air out and just dehum the air that is down there.
As far as ground gases. Radon is the big one that I have heard talked about. Here's a website to check that out. http://www.epa.gov/iaq/radon/
You can order a kit from them or go to your hardware or home center and buy one. To test for radon isn't expensive. You just hang a cardboard packet from the ceiling in the lowest living level of the house for 10 days and then mail the packet in. They will send you back the test results.
Do you have any water down in your crawl space?
Do you have plastic spread?