Anyone an expert on crawlspaces?

[LaydeeBug]

Mine has flooded and I just replaced me sump pump. I want to insulate underneath, but am not sure what I should use, and whether or not it is ok to staple insulation into floor joists.

I am getting ready to build a new crawl space cover, but want to try and get the most savings on my utilities. (and leave a smaller foot print)

[NYC_SKP]

1. I would talk to a local building supply house, and older person with experience.

I think your region and climate and details of construction might indicate different solutions than others might use.

Ordinarily, I think thick foil faced bats stapled in place would be fine.

The only installation I've ever seen done used chicken wire to keep the bats up, not a bad idea since gravity will, sooner or later, have your insulation hanging down in places.

Check with the locals, they'll know what to do. And try to get more than one opinion about it.

[LaydeeBug]

2. Those are all great ideas...thank you for them. nt

[pscot]

3. Two things

You have to allow air to circulate or moisture will get up into the house.

You need a vapor barrier between the ground and your floor. Jacketed insulation stapled between the joists is fine. Face the foil or paper side down. The insulation comes in 6 foot batts, either 18 or 24 inches wide, depending on the joist spacing. Screen all vents. Critters love the fiberglass; it makes nice warm nests where they make lots more critters. They'll make a shambles of your expensive insulation. It's possible to do it yourself if you're reasonably handy. You can get spring thingies that bend up between the joists and hold the stuff in place. It's not a pleasant job. Good luck.

[LunaSea]

4. Good advice above..

Locating the source of, and preventing the water from getting in should also be on your list.

I like the chicken wire suggestion for hanging, but it occurs to me that a finer mesh of hardware cloth might be a better choice for keeping mice out of the insulation.

This site on chicken coops has a nice explanation of the differences-
http://www.the-chicken-chick.com/2012/11/coop-security-hardware-cloth-vs-chicken.html

[jeff47]

5. Just to answer a specific question the others missed

Yes, you can staple the insulation to the floor joists. If you use paper-backed insulation, it'll come with a stretch of paper that is beyond the fiberglass. Staple that to the bottom of the joists. And make sure the paper overlaps the next insulation, so that you have a continuous vapor barrier.

If you can't make it overlap, there are rolls of vapor barrier you can use to cover the wood.

[Wash. state Desk Jet]

6. How much water gets under there ?

Yes the insulation will make a difference. Staple is good a way as any. Chicken wire is a lot of work . I've used string in a criss cross
method to hold it up.I've use lathing, I've used steel rods too. The insulation does drop down in places from time to time, but since you have a pump under there you check on that from time to time so you can keep an eye on the insulation too.

Throw down sheet plastic /Biscayne as a vapor barrier ,thats always good thing to do.

All the advice given to you is first rate.

It's always a good idea to get a consult at your hardware store ,home depot wherever, someone that works in lumber,knows about insulation,gutters ,concrete all that. The thickness of yer insulation is determined by the width of yer joists and the width of yer insulation is determined by the spacing between yer joists.16" 18'"so on . And to determine how much insulation you need of course,
you must do the measurements. ! It is not uncommon in older homes for the spacing between joist to vary somewhat although
the spacing should be consistent with the occasional off measure-.usually the off measure is less than the standard-if it's 18 "'s on center there may be a few 14"'s or 16"'s in the mix, end the run ,chimneys and other such.





Good luck with your project.

[LaydeeBug]

7. a-LOT. I have to get new or build a new crawl space cover.

and get the cat fixed, and paint, and...

you get the drill