All,
I’m from Fine Woodworking but my son asked a question about his basement floor. His house is about 70 years old (craftsman style) with a poured foundation that measures about 40×24. The slab has a rather large crack going from side to side that makes a bit of noise when he walks on it. There are some other smaller cracks, one actually moves when he steps on it.
Teh question is what should he do about it. Repair? Replace? Ignore? thanks
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Replies
Concrete gonna crack.
Movement is not good.
"Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
bulldozer
Call a mudjacker for his opinion. These guys drill a 2" core out of the floor and pump in a cement grout under pressure. Raises sunken areas, fills voids, etc. Cheeper than replacing. If it's too far gone, he'll tell you.
If it is 70 years old, I'd get a hammer drill and a small bit and drill a few holes down thru and see how thick the floor is. If it is really moving when he walks on it, it might be a slurry coat or a thin coat of concrete just to make the floor broomable.
If that is the case, a sledge hammer and a few kids might be just the ticket for ripping up the loose areas, raking out and repouring.
If it is a thick floor, I like the idea of a mudjacker but dont know any in my area.
Was the floor always like this or has it changed over time since they bought the place?
Jeff,
My son bought the place a few months ago so there is no history and I have not seen the house yet. He's down in the Haverford, PA. section so the mudjacker availability may be an issue. If he leaves it alone what are the consequences?
Hey, I am right up the street in Chadds Ford.
The basement slab is not a structural part of the home unless there is a post dropping down onto it in the vicinity.
Typically the beam that drops down to the slab actually is supported by and additional small pad of concrete under the slab or in an older home, oftern they just put a concrete block there to support the post.
So, since it is likely non-structural, doing nothing right now is likely ok except for a trip hazzard and perhaps not pretty. (I trust that the cracks dont go up the walls as well, as they are structural)
I have seen both very thin and fairly thick slabs in this area in older homes so it is a #### shoot as to what the builder did in his basement. (I have seen 1 1/2" and I have seen 5" of concrete in the basement slabs)
Hope that helps
Jeff,
I thought I detected a Chadds Ford Accent...lol.I'm going to copy the comments and email them to my son. With a new old house there are lots of opportunities to spend money. Thanks for the help
Hey BG
Geez, you have taken this computer stuff to the next level.
Detecting the accent!
I am in the wrong business. lol
Yep, all homes suck money but at least some day if you sell em you might get some back.
agree that seventy years ago a lot were poured thin and no re-inforcing, just something to walk on clean - called a mudslab. If it moves, odds are good that it is thin and that water moving through the soil under it has washed some of the supporting soil away. Grouting is a probabl solution.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Is a mud slab similar to a rat slab?"Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
yes.One is to keep the mud down. The other is to give the rats a clean surface to crawl on;)
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
"Typically the beam that drops down to the slab ..."????You mean post?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Yes, I mean post, or stantion, or lolly column.
Sometimes my answer depends how much I drank and which way I am oriented.
Had I been upright, I would have said post, however I may have been sideways and said beam. lol