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Damp pea gravel in the half crawlspace


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I recently saw a house design that was a bit unique to me. The house is a large four-level split with a half basement and the other half is a crawlspace. In the crawlspace, half of this area was a concrete slab, the other half was pea gravel. The concrete slab was dry and there was not much efflorescence to be found and no discernible smell unlike some I have seen.

The pea gravel, however, was damp to the touch the entire way through and across the whole area it covered. Two teleposts were plunged into it and had rust residue near the base indicating this was likely an ongoing dampness. There was some poly loosely draped over it but definitely not sealed off.

We were looking at purchasing this home but we're quite concerned about this. What are you thoughts on this situation and things we should look for more closely? We plan to take another look at the home this week and wouls get a home inspector in prior to purchasing but would like to save that only if this isn't something that would completely rule out consideration of this house. This is not an area we are particularly knowledgable in.

Thank you

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With loose poly over the gravel I would expect it to be damp. There is moisture in most soil and the poly typically allows it to condense and not evaporate. That may not be a big concern.

I would be more concerned about the columns. They may not be rated for permanent support, they may be deteriorated, they may not have proper footings, and why they are there is also an important question.

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Thanks for the reply. Next look I'd like to dig out around the teleposts and make sure they are on piers. The posts down there are under a beam that seems to run across the entire crawlspace and hold that part of the house up. That said one of them is very bent at the top which I would guess is from a major shift at one point. There is also a large hump in a floor upstairs in one part and I wondered if that could be from the house sinking around a post and the post pushing up on that area? This whole area of housing is but on a clay base so there is often lots of moving.

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Builders use pea gravel around here as a way to elevate the floor of the crawlspace above water infiltration. It provides a relatively stable, comfortable-to-crawl-over floor that allows the vapor barrier to lie flat and get good coverage. It doesn't eliminate the water infil but it's not intended to; this is a way of managing the infil. As long as crawl ventilation is working OK and the infil never comes above the height of the gravel those houses seem to do fine.



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