Saturated crawl space

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Yod12

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I have a 900 sq ft crawl space I went in after all the heavy rains. Fiberglass insulation on the 'ceiling' was dripping, saturated. It's extremely muddy, and I noticed running water coming down a gentle slope. I followed it and came to a spot in the middle of the house. I didn't know where it was coming from. I dug down about five inches and hit water. I could see it coming in from somewhere, but can't trace the source. I figure there's a high water table here.
So I put a sump pump at the lowest point where the water was coming from. I wonder if this is the best place for it after it dries up a little.
I need to take care of this problem. I don't know if a sump pump is the answer.
A contractor quoted me $10,000 to correct the problem with a trough along the perimeter of the northside of the house outside. He ended up charging $18,000 and didn't correct the problem at all.
 
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Ouch.
So some more detail to what the contractor did, maybe we can use that.
Did he run a drain around the house?
Did he water proof the foundation.?
Does the water run away from what he did or is it pumped away?
 
Is the house supported with piers or a full foundation? What area of the country do you live in?
In line with Sparky’s question is there a plastic vapor barrier on the bottom of the joists below the insulation?
 
Hey, thanks guys. Haven't been able to get on here for awhile. The ground underneath the house is very rough terrain. I guess someone threw this place up in a hurry. There's very little room to literally crawl in there - and one 90 sq ft section is two feet between the ground and joists - no room to get in there at all. There's a concrete perimeter foundation, but posts and piers support the middle of the house. I just noticed one of the piers is cockeyed - sank into the mud at a 30 degree angle - looks really weird, but somehow the post is straight.
There's no vapor barrier - I'm not even sure what that is.
Had a dehumidifier in there for years, but it just died. Not sure if it did much good.
 
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Is the space vented?
A lot can be done on the outside to stop the water from getting to the inside.
Is there working gutters with down spouts long enough away from the foundation?
No flower beds forming holding ponds?
Grade running away from the foundation?
Outside of the foundation waterproofed and all holes sealed where things like plumbing where run?
May even need a french drain.
It would be rare to find an older crawlspace graded out so a vapor barrier can be easily be laid out, 2' is more than enough room to get in there and try to level it out the best you can and add one.
Take a look at the subflooring and floor joist under there.
If there's black fungus growing on them they can totally destroy the wood my eating the cellulose that holds the wood fibers together.
 
In trying to keep my 900 sq. ft. basement free of mold (35% to 50% RH) I bought what was supposed to be a dehumidifier that was oversized for the application.
On humid days it could only get down to 65% according to its digital display.
Fortunately, a neighbor soon threw out an old Kenmore unit. Two hours later I had this working and now both of them together can maintain 50% on sticky days.

My choice was a lump sum of $30,000 to excavate the foundation outside, with a questionable outcome, or pay PoCo 15 cents per kwh for the foreseeable future. It's kind of like I'm paying PoCo an annuity.
Both together running full or part time maybe take 1200w, which will about double my present electric bill for those days that are humid (maybe 1/6 of the year).

The lump sum you will pay to make your space "conditioned" should be way less than 30 kilobucks unless you keep having to do more to get to your target humidity level.

As an aside, a sling psychrometer will give you a pretty accurate measure of your RH and half of them on Nextag cost between $85 & $48.

Another thing which I just learned.
The excavation for your house may have its own artificially high water table, as if the hole doesn't let all the water seep out like normal, undisturbed soil. It's a permeability issue.
 
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Is the house supported with piers or a full foundation? What area of the country do you live in?
In line with Sparky’s question is there a plastic vapor barrier on the bottom of the joists below the insulation?

We never want to make it sound like we encourage anyone to put plastic on the bottom of the joists.:hide:
 
With 27,000 hits on the subject of placement of vapor barriers, your job is to separate fact from opinion. :help:

IIRC it changes with the normal climate for the area you're in.
Somebody should invent a vapor barrier that adapts to its environment and doesn't break the bank.
 
With 27,000 hits on the subject of placement of vapor barriers, your job is to separate fact from opinion. :help:

IIRC it changes with the normal climate for the area you're in.
Somebody should invent a vapor barrier that adapts to its environment and doesn't break the bank.

Did you find someplace that called for vapour barrier on the bottom of the joists. Other than mobile homes.
 
Did you find someplace that called for vapour barrier on the bottom of the joists. Other than mobile homes.
No.
You may know of a specific rule that is always correct for non-mobile homes, in which case the OP should go with your recommendations.
It's been quite a while since I researched this particular topic, so my info may now be obsolete or I have remembered it incorrectly.

I should tell you that I have been invited back to this forum, either by software that flagged me or some person on your forum. There was no name on the e-mail.
If this is in error, please disinvite me. It's all good. :thbup:
 
No.
You may know of a specific rule that is always correct for non-mobile homes, in which case the OP should go with your recommendations.
It's been quite a while since I researched this particular topic, so my info may now be obsolete or I have remembered it incorrectly.

I should tell you that I have been invited back to this forum, either by software that flagged me or some person on your forum. There was no name on the e-mail.
If this is in error, please disinvite me. It's all good. :thbup:

Whether you are invited or not would be non of my business.:thbup:
 
I just don't know what to do about the water getting in there - if the water table is high (how can that be artificial?), no amount of outside prevention is going to stop it as far as I can see.
Thinking about putting another dehumidifier in there again. Store bought models are about $200 or so. I've seen crawl space dehumids for over $2,000. How can there be so much difference?
I'm in California near Santa Cruz - mild climate.
 
The out side of the foundation should be waterproofed (looks like tar when done.) to below the level of the fill inside the crawl space.
Perforated drain pipe and gravel around the house at a level same as water proofing and drained or pumped away from the house.
Then cover seal the crawl space dirt with 6 mil poly. Make sure you have enough cross ventilation in the crawlspace.
 
I just don't know what to do about the water getting in there - if the water table is high (how can that be artificial?), no amount of outside prevention is going to stop it as far as I can see.
Thinking about putting another dehumidifier in there again. Store bought models are about $200 or so. I've seen crawl space dehumids for over $2,000. How can there be so much difference?
I'm in California near Santa Cruz - mild climate.

I would also want to know what sort of terrain you are in. It sounds like you are not seeing signs of water penetration at the walls, but are seeing it at the low laying part of the crawl space. To me that would generally mean hydrostatic pressure.

You mentioned looking after it rained, but I would be curious if you find it when it hasn't rained or if you have noticed a seasonality to it?
 
As I mentioned earlier, it's very rough terrain and not too much fun to crawl around in there.
Rainy season here is late October to April. It stays saturated until August, September, but as you may have heard about all the floods we had last winter, it may not dry out until Sept if at all.
 
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