Crawl Space Insulation

[Gary]

What is the proper way and the proper materials to
insualte a crawl space. The height of my crawl space
varies from 18″ to about 10″ and there is already a
dirt floor barrier of plastic. I have Hot Water
baseboard heat (the pipes are in the crawl space and
also uninsulated) and I fear I’m getting quite
a bit of cold from the floors in the living areas.
On cold days, the furnace runs quite a bit.

Gary

[Jay J]

Gary,

It’s gonna be a dirty job but there are a few things you should address.

Wrap ALL your piping in the crawlspace. Measure the the width and length (as best you can) and go to the Home Center and get the proper pipe insulation. Then, install fiberglass batt insulation in between the joists, paper side up. Then use either chicken wire to nail to the joists underneath to keep the insulation from falling out. (Those joist hangers are no good in my book.) Or, what I did was pound a bunch of tack-nails about 1″ long about 3/4ths of the way into the bottom of the joists, and ran nylon string around them, from joist to joist, nail to nail, to keep the insulation up. (I kinda made like a spider web.) In the space you’re talking about, it might be difficult to work with chicken wire.

At the ‘ends’ of the joists (what’s called the ribbon board), cut small pieces of the fiberglass insulation, and ‘stand’ them up on the ends, paper side in. Don’t close off your crawlspace because you’ll force the humidity into the house. (If it’s already closed off and you aren’t having any problems, let it go.)

If you need more info, post up. My best to ya and hope this helps.

Jay J

PS: Use something like R-30 or R-36 insulation. Measure the ‘width’ of your joists because your insulation should fit ‘comfortably’ in the joist cavity. The insulation packaging should tell you what type of ‘cavity’, or space, the insulation can be used in. You see, if you buy an insulation that’s waaaay to thick, and then you compress it to fit, you’ve defeated the use of the insulation. It needs to be ‘fluffed’.

[The Insulator]

DO NOT INSULATE THE FLOOR JOISTS! That isolates all plumbing below it from the source of heat. Even if the pipes are insulated, if left unused, it will loose all latent heat and freeze.

I recommend the following. 1/seal all crawlspacw venting air tight; 2/ Insulate the foundation walls (Foam board works well); 3/include your crawlspace in your heating (Your floor is only as warm as your crawlspace, unless you have in-the-floor heat. I’ve used these measures with dood success.

As far as your furnace running a lot, I suspect that your cold crawlspace may be a symptomn of a greater problem. Air is probably leaking out of your house (Probably into your attic)and being made up by outside air being draw in low (Your crawlspace). Other syptomns would be snow melting & ice building up on your roof. Solve the leakage problem, and other problems will be gone or minimized

Yhr Insulator

[Lisa Joslin]

Has anyone had any experience with this “system”? My crawlspace is the full length of my 38 yr. old home. I had to go down there because of mice…noticed all the insulation (on floor joists) is all falling down. (Whoever installed it, did it backwards…the paper is facing the “ground” and the fluffly insulation is facing the floor of the house). There is a LOT of moisture on the “plastic” lining the ground. (It is “vented” as well.) I’ve been doing a lot of reading and am concerned about all of this moisture. Was wondering if anyone has had experience with Neutocrete….

[Author]

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