Sinking Patio

[Richard in Smithville]

My patio in the back of my house is a 20x10 solid concrete slab. The slab is sinking along the length closest to the house. To add complications, my furnace, which is an outside combination unit, also sits on this pad. Is there some way to stop the pad from sinking with out the extra work and expense of removing the furnace and then putting it back again?

[gjat]

Check out 'pressure grouting'. Basically a company can come out and pump concrete (without large aggregate its grout) under pressure and can lift the slab. I have no idea what it would cost to lift a slab, or if it's too minor a job for them. Here in florida, it's used alot to stablize some types of structures in various soil conditions.

[JoeyGee]

Check out 'pressure grouting'. Basically a company can come out and pump concrete (without large aggregate its grout) under pressure and can lift the slab. I have no idea what it would cost to lift a slab, or if it's too minor a job for them. Here in florida, it's used alot to stablize some types of structures in various soil conditions.

Is that also referred to as "mud jacking"? I think I saw that on Ask This Old House once.

[twistsol]

There is mud jacking, sand jacking and the concrete jacking mentioned above. They are pretty much the same other than what is pumped in under the concrete.

It isn't cheap and costs about half of what replacing the slap would. After we got quotes, we chopped up the concrete and put in a wood deck.

[LCHIEN]

if your patio is sinking right next to the house then i'd be more worried about the house than the patio!

[woodturner]

It isn't cheap and costs about half of what replacing the slap would.

My guess is that prices vary widely, and probably by region as well.

For my foundation repair, the mudjacking option was the cheapest option by far at $1500. However, that is mudjacking a footer, not a slab. To mudjack a 10 x 20 slab in this area costs around $500, while replacement of the slab would be more like $2000.

One of the surprises in getting estimates for my foundation repair was the wide range of estimates for the same work. I'd get five or six estimates for the mudjacking before deciding - finding the right contractor may be the key to making this approach economically viable.

[gjat]

I've never heard it called anything but pressure grouting. My experience is using it to stabalize roads or traffic signal poles. I would expect a grand as a basic price, but again, I am only familiar with larger scopes.

[Richard in Smithville]

That helps a lot guys. Thanks for the the info.