Crawl Space moisture problem

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dgarrity

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I purchased a house about 4 years ago and a year ago I started noticing that my floors were uneven as you walked from one side of the house to the other...it reminded me of a wave, a little down, then back up, then down again. My flooring is a combination of carpet and wood flooring and the wave is more apparent on the carpet. I had a company come out and they went into the crawl space and installed some beams to support the floor in these places, but 1 year later the flooring is wavy in another area.

My house has a vented crawl space of about 24 inches with no insulation. It is 43 year old home in South Carolina close to the beach so there is a lot of humidity and there is moisture in the beams and some dry rot. I have had 1 company recommend that I have a crawl space vapor barrier installed along with sealed vents and a dehumidifier for a cost of $20,000. Then another company suggests having the underside of the house spray foamed with a closed sell insulation foam for about $8500.

I would appreciate any advice on this problem as I do not know what to do and I would like to sell the house, but need to fix this problem first.

Thanks!
 
You may have a moisture problem but should not effect the floor as described.

I think the floor is more about the foundation. It is common to support a sagging floor but if that is not supported properly, other problems can show up.
Keep in mind that you can call any company does any kind of work and they will find something they can fix, whether that solves your problem or not.

Tell us about your foundation.
And welcome to the site.
 
if you have a moisture problem.
where is the moisture comimng from?

where does your dryer vent terminate ?
open sewer ?
water leak ?
water coming in from outside thru walls ?

dehumidifir has a filter,needs to be cleaned every month or it will stop working

if you rule out each of those, move on to foundation.
this time of year is wet, that means the ground will swell up causing upheval
is the ground around your home wet?

your house should sit above the surrounding land scape, and the ground should be graded away from the house a minimum of 10''
 
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There are no sewer leaks or open water or water leaks or any evidence of water. I am told the moisture is coming through the ground and the humidity of living in the south near water. The moisture reading was 18% and supposedly 24% is high and 13% is ideal. I believe the foundation is pier and beam
 
------Welcome to the forums!----------

You are correct; local problem, the solution; http://www.advancedenergy.org/portal/crawl_spaces/pdfs/Builder Online Article - 2005.pdf

Save energy; http://www.advancedenergy.org/porta...sture Solution Becomes Efficiency Bonanza.pdf

Check for radon before closing it up; https://www.epa.gov/radon/epa-map-radon-zones

Another local paper from Princeville, NC; http://aceee.org/files/proceedings/2010/data/papers/1929.pdf

Use the left over floor joist cavity fg insulation in the attic, remove any face papers first. In fact, air seal the attic first to limit air infiltration/exfiltration. open some intake vents from the house and add exhaust vents, cover the dirt with plastic to condition the crawl per code; http://www.google.com/url?sa=t&rct=...cxhZUUbjb19gdOLGMmhxgpg&bvm=bv.59026428,d.cGU

The wood flooring could easily be buckling from moisture rather than the joists, especially as said- it moves around;photo 2; http://buildingscience.com/documents/insights/bsi-023-wood-is-good-but-strange

Gary
 
GBR/Gary,
Thanks for your help with this problem. I keep getting conflicted advice...everyone has a different solution for the problem. Any advice on who to use to have this work done? So far I have gotten a quote of $20,000 which is more than I want to spend on a 43 year old home of about 2400 sq ft.


Kind regards,

dgarrity
 
GBR/Gary,
Thanks for your help with this problem. I keep getting conflicted advice...everyone has a different solution for the problem. Any advice on who to use to have this work done? So far I have gotten a quote of $20,000 which is more than I want to spend on a 43 year old home of about 2400 sq ft.


Kind regards,

dgarrity

Spend $500 to $1000 on and engineer to inspect the floor from below, have him write a scope of work to be done contract him to inspect the work when finished.
All your contractors will be on the same page.
It is not uncommon to have a contractor disagree with the engineer or find more when work starts, but the engineer makes the decisions.

If you don't know enough to choose whose BS to believe the engineer is the only way to go.
 
"If you don't know enough to choose whose BS to believe the engineer is the only way to go. "------ I agree with that. Especially just getting opinions from some of your sources rather than facts (with links to back them up) to help find the source of your problems. Being there goes a loooong way to fixing the problem. Pictures of the crawlspace would help a lot... then we might be able to "see what you see"...

Gary
 
nealw and GBR,

Thanks so much for your suggestions. I like the idea of having an engineer inspect the floor.

I have included some pictures of the crawlspace and would love your thoughts.

Thanks,

dgarrity

Under the house 1.jpg

Under the house 2.jpg

Under the house 3.jpg

Under the house 4.jpg
 
nealw and GBR,

Thanks so much for your suggestions. I like the idea of having an engineer inspect the floor.

I have included some pictures of the crawlspace and would love your thoughts.

Thanks,

dgarrity

The crack in the last picture is something an engineer should look at. They hate it when people notch timbers and that is why.
 
Anytime wood is notched like that it creates a weak spot.
What I've had to do many times in older homes is inject some Tite Bond into the cracks, jack up the beam, Then sister the whole beam using constrution adhesive and ACQ approved ring shanked nails every 12", making sure to nail every other one high and low.
Then install a double beam joist hanger.
 
We had something done very similar to what you described...just worried about the moisture in the crawl space now.
 
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nealtw,

An engineer has looked at the cracked beam and it has been fixed. Just posted the photo so you could see what the condition of the wood is in the crawl space so you could advise what I need to do to get the moisture out of the crawl space. One company recommends that I have a crawl space vapor barrier installed along with sealed vents and a dehumidifier for a cost of $20,000. Then another company suggests having the underside of the house spray foamed with a closed sell insulation foam for about $8500.

Thanks,

dgarrity
 
If you have water below that has to be dealt with first, has the foundation been waterproofed below ground level, is there a perimeter drain at the bottom of that, is the sheet poly covering the dirt inside the crawlspace.
After that then you can figure out if you have enough venting for fresh air to keep it dry like has been used for hundreds of years or spend 20,000 on closing up the crawl space so you can have the expense of a dehumidifier running for ever.
Spraying the floor with foam is great insulation but that still leaves the framing exposed.
 
We have not been able to find any evidence of water under the house, but your comment about the foam being a great insulator, but will still leave the framing exposed really made sense to me as I had the same concern and I am not experienced in this area at all. So is the only other option be closing up the crawl space?
 
Who measured the moisture level in the wood.
High humidity in the air will show up on cold water lines as water condenses on the pipes.
Sealing the crawlspace would mean that every nick and cranny that would allow air to enter or leave the house thru the floor.
They say dehumidifier but really it should be conditioned space and then you will really have a problem with you radon.
I would do the perimeter drain as described and the poly and what ever you have to do about the radon and put a vent fan in and keep the air moving, insulate any cold water pipes down there, you just by foam covers that slip over the pipe..
All this work will have to be done regardless of what you do.
 
I do not understand why I would need to do a perimeter drain as there is no water under the house and no drain pipes under the house. And I do not understand your comment about radon. Please advise.

Thanks,

dgarrity
 
I know little about radon but I suspect there are levels, some will be removed with cross venting, the next level would need roof vent and at some level would need power venting thru the roof.
What ever you do with the crawlspace, requires that water from the ground is impossible or as near to that as you can, so no matter what you are going to do you should always have the dirt covered, and drained.

A lot depends on what the source of moisture is.
Moisture from the air has been dealt with for hundreds of years with just passive venting.
Moisture from the ground, that can not be detected by eye.
As the crawlspace is always just a little cooler than the inside of the house, warm moist air from the house can be forced thru holes in the floor and with the crawlspace being a little cooler that moisture will condense on any thing down there.
So as I suggested earlier, get an engineer that specializes in moisture problems to look at the whole situation.
 
Good advice!! I will get an engineer to look at the whole situation.

Thanks again,

dgarrity
 

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