I have an old house with a low ceiling basement approx 5′-10″.
The foundation is brick, 3 courses thick.
I want to lower the floor and replace the foundation with cement block.
I have gotten suggestions ranging from moving the house into the backyard, removing the orignal and putting in a new foundation to putting in cement block columns every 10 feet at the perimiter then replacing the rest of the walls.
PLEASE HELP
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Replies
Please explain why you want to replace your foundation instead of "just" jacking up the house a foot or so and adding on to your foundation. It's a big job either way.
If you are really going to replace the whole foundation, you should probably move the house , excavate and pour new foundation with room to work, and then move house back.
zak
"so it goes"
I can not "just" jack up the house because the house is at the maximum height allowed by my village.
I was denied a variance.
With many such jobs, the house gets jacked up and set on crib work. This means disconnecting utilities, heat, etc, A new foundation is put in place and the house dropped back down. They don't get moved if it's not necessary.
Beat it to fit / Paint it to match
I agree with hammer1, you don't need to move the house. Just jack it temporarily (my own went up two feet during the process), dig the trenches, pour the walls and set it back down. At that point you can finish digging out the remaining dirt that was holding up the cribbing piles. Of course, your new walls, block or otherwise, need to be deep enough to allow the headroom you're looking for.
Do you want to increase the head room? Do you know how deep the foundations are? What is under the brick? What type of soil? Water level?
Underpinning to increase headroom can be done, but you have to know what you are dealing with, particularly with the brick walls.
...that's not a mistake, it's rustic
Thr reason for digging out is to increase head room.
The brick walls are even with the floor, nothing below floor level.
The soil is heavy clay.
The water level is well below floor level.
ah-ha! Bumping into ordinances overhead, eh?Well then you can support the house in place and dig down, but you should definitely plan for water problems. I speak from experience. Unless yopu live in a very dry desert place, water will find its way to your trenching and possibley undermine the cribbing. You MUST have a way to deal with this. dig the drains first - below the deepest that you will dig for the new footings.I would not use CMUs either. not below grade anyway
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What are CMU's?
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WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
cmus are concrete masonry units. Weakness is at the bonds.
clay soil is expansive. when it absorbs water. some cclays can expand up to three timestheir volume, so it can place tremendous lateral pressure on a CMU wall. I'd have a hard rtime thinging of some portion of a building where i have seen more failures ththan cconcrete block with improper backfill. if you do a CMU foundation, iuse ladder wythe and rebar and then backfill with clean gravel over drain lines
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I have much the same problem and have been studying solutions for 20 years and have never had the money to fund any of them. I do need to jack the house about a foot, but need to add the the depth of the basement (dirt floor)also. Best solution seems to be jack and cribb. Old House Journal has had many articles on this subject. When I get the money I'll jack the house a foot, cribb as necessary, tear out the old sandstone walls, build new block walls up to the bottom of the 8" X 8" hand hewn oak plates and gently lower her back down, remove the cribbing, dig out the floor, pour a new concrete floor, re attach all the mechanicals, and voila!. Piece of cake. Or they'll drag me out of here feet first with a 5' 10", dirt floored basement still in place.
I don't think I would use a cement block foundation in heavy clay.
WHY NOT A CEMENT BLOCK FOUNDATION IN HEAVY CLAY?
I am fairly ignorant about other types of foundations except their prices.
would cost a fourth as much to just jack the house up and add a couple feet to the brick walls
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!