Subfloor on slab?

[anthonyeh31]

Hello, my wife and I have bought a small house in the northwest. I have two big questions for all of you. The first is, the original house or hut was put on a small wood foundation. The crawl space is only approx. 8 inches. Then at one point in time, someone poured a concrete slab foundation in a "U" shape around the original house. Now the slab has cracked. It runs the depth of the house. Also, someone has removed the old roof, including the trusses, and has replaced the whole thing with new trusses and roof. When I went up to the attic, there is, depending on which part of the house you measure, approx. 16 to 24 inches where the sheetrock on the ceiling in the house is, to where the bottom of the trusses are.

Also, the crack has been there in the slab supposedly for 20 years. I was told that the last people just put their bed over it. It is also unlevel up to 1 to 1 1/2 inches.

So here is what I was hoping to do. Grind the crack down on the high spots. Fill with some kind of epoxy. Put a wooden subfloor over the slab of concrete. Tear down the ceiling and raise it, so it fits on the underside of the trusses. I believe if I do this, I can acheive a 8 to 81/2 foot ceiling.

I know that there are some of you that probably can tell me what to do and what not to do. Please feel free to let this greenhorn know what is what.

Thank you for your time.  

[glenn kangiser]

I don't know about the unevenness, but you don't need epoxy.  It's expensive -- just use concrete bonding agent - looks - and probably is similar to Elmers glue then uses sand and cement about 3 or 4 to 1 , mix it and fille it as desired when you are tired of grinding.  The new diamond stones on a portable grinder are probably best.  Note that if the floor moved and cracked it probably will continue to do so unless the adjacent tree roots are cut off and stopped from growing under it---just guessing.

[John Raabe]

If you have not closed on this house, you need to have a structural review of the place as a condition of the final sale.

It sounds to me like there is enough oddball stuff and potentially serious problems that you need an experienced builder/architect/designer and perhaps a structural engineer to look at it.

You need to know why the slab is cracking, if it will continue, and if it can be repaired. Also, what is going on with the roof and why was it built so low?

Cobbled together old houses can have real serious problems. I inspected one last year - after the fire!! Fortunately everyone was safe (they were having a dinner party at the time). It started from a candle on the fireplace mantel in a room where the ceiling had been dropped to 6'-6". The roof was a maze of cavities and layers of old dry materials. It smoldered for hours and ruined the whole place. I don't think the insurance even came close to repairing the damage.

The owner should have called for an inspection BEFORE she bought the place. And she was a real estate agent. Should have known better! :-/