We have a new 18 month old house built by myself for my family. The other day I thought the gaps below some of the baseboards looked a little bit wider than usual. Curious and concerned, I went below to the crawlspace for a closer look, and sure enough, there was a quarter inch gap above the piers and below the two main floor beams. We’ve had an unusually dry fall, and the wooded hillside we’ve built on is full of clay soils, which have dried up and contracted. Come the Spring, the soils will expand with the seasonal rains, so I’m hesitant to shim the gaps, thinking they’ll push the structure up too far when the clay does expand. I’m wondering if anyone knows of a product/technique/or system that automatically compensates for soil expansion and contraction, like a spring-loaded, load-bearing, self-adjusting wonder gizmo. Any thoughts?
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There's no reason for the soil in the middle of your crawlspace to get wet again, is there?
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Actually, it probably will. They call this topography 'karst', and it's really weird... lots of lateral water movement. I've worked on older houses on the top of good sized hills where there are as many water issues as at the bottom of the hill, and not from roof runoff, but from water moving up and/or laterally.
Hmmm, well I'd have made allowance for that with drainage but since it sounds doubtfull...There is a Japanese technigue - you slide a shim in from each side - opposing each other - just enough to touch and keep the bounce out. They make allowance for the thickness they take up ( maybe two or three inches) and visit them every month to make adjustments with the seasons. Some are quite elaborately carved when in visible locations.
I've done a couple from fir or oak to save a job in special circumstances. .
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Tim,
I think I would try Piff's way for a season and see what the shims do over time. If they don't move a whole lot then try shimming it permanetly. If you are always having to fiddle with them then you have the flexibility to do that as well. I tend to agree with Piff that the center of your crawl space shouldn't get wet again but only time will answer that question. I suspect that the soil in the crawl space has dried out since the house has been built and hopefully will remain stable from this point.
Mark
>I suspect that the soil in the crawl space has dried out since the house has been built
Can we be sure?
What's the drainage situation like? Are there perimeter drains? Do the gutters all exit downhill? Or is it likely that when rains return, there will be water that can work its way under the house?
Cloud,
I didn't say we can be sure. That is why I told him to try Piff's shim method first and that time would answer that question. I would say there is a strong chance he won't have any more problems and if that proves to be the case he can fix it permanetly.
Mark
Mark, that wasn't meant as a challenge. More a way to solicit info from him on what the current grainage is. For example, if the gutters on the uphill side drain to that same side rather than run downhill of the house, then he's more likely to have water return to crawlspace.
Cloud,
Allright, I'll let you get away with it this time, But next time you get 50 lashes with a wet noodle. LOL Have a good one.
Mark
oops... did leave out the fact that perimemeter drainage is excellent... a french drain runs the full footprint and runs like a faucet when it rains. We are in NW Arkansas, lots of wooded hillsides the locals like to think of as mountains but are more like rolling foothills for the Ozarks range. In the Spring, some of the hillsides- including ours- develop wet-weather springs and will stay persistently wet, so we knew drainage would be essential. But hmmm... watering my basement?...in a peculiar way it makes sense, but old school screams "what..you nuts?" The french drain will carry off whatever surface water might reach it on the uphill side,and any water above the footing, but water travelling laterally below that- and it's there- will enter in the crawl as the grade traverses the hillside for the length of the building. That water seems to travel under the plastic vapor barrier and can eventually drain out from the lowest corner of the building where a drain is installed. It's never enough to justify a sump pump, so the issue boils down to wether or not it's enough h2o to cause expansion back to the original grade. If so, any installed shim will create a crown situation for the beams, which seems as potentially damaging as a sag. I was considering milling down some dense hardwood flat shims, actually more like a flat plate,and installing them. But a plate would be a bear to remove if things started to tighten up, so a tapered shim that won't crush seems to be the way to go. That, and a close eye.
That's what I was alludung to in my ref to Jap method. Go for it and keep an eye on it..
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Living in a house built on clay, I can tell you that it has tremendous capillary action and holods a LOT of water. Moisture can migrate under the footings and drain system. Our crawl space can be bone dry in the fall and almost swampy in the spring.
It still goes back to a good, well designed and installed drain system.
Maine has plenty of clay and water. When I moved here, One guy I was working with had the attitude, "this is wet ground, you can't have a dry basement, so there's no use trying"
He used it as an excuse for sloppy workmanship.
I figured, "B S " and wen to work doing it right. All the underground work I did is dry.
It's not hard, Water follows the path of least resistance and gravity still works, in spite of govt regulations, LOL
Keep those two facts in mind and you can stay dry..
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Piff,
Amen to that brother, well said.
Mark
Tim,
Where are you located?
I have heard that there areas in Texas where they advocate watering next to foundations to keep the clay soil moist.
My experience is that there are different types of clay and what works in one area might not work in another.
________________________________________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
Hear that, Piffin?
Huh?
Guess not.
Maybe you could say it a little louder or more clearly. Diction is important when you speak to us deaf old geezers..
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
My experience is that there are different types of clay and what works in one area might not work in another.
Point is, Piffin, maybe saying, "BS, etc,etc." won't solve the problem everywhere as you suggest. I can tell you that my footings would have to be on bedrock to stop the lateral (under the footings) and then vertical capillary action of water. Gravity is only a piece of the picture.
Humble pie is good with whipped cream.
Well, you still missed what I had to say.
Number one, the bs comment was directed at the guy here, not you, so don't get bent out of shape.
But what you missed is that if you give the water an easier path to follow, it will go that way. Perimeter drains will catch the lateral movement and lead it to the sump or the daylight. If the soils are so wet as to allow ground water to siphon to the basement or crawl space, then more drains are placed within, in a bed of stone or gravel. That gets covered with a vapour bar and sand or concrete. It can be dealt with. There's always a solution.
I hate whipped cream, but I'll share the pie with you..
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
I've always lived in houses on clay - in Oklahoma, most of the houses do not have crawlspaces - it is really important to water around the house in summer.
I used to be more concerned about conserving water until a really dry season - we started to see new cracks (wrinkles around the eyes?) in our 38 year old house - then we decided to put the house on the market, and started watering the lawn like crazy, because we all know how important kerb-appeal is...... and the cracks disappeared.