slab jacking question

Our 1800 square foot house was built in 1976.The corner bedroom is settling and the outside wall is cracked by the window.The bricks have a 1/4 inch or more crack down the wall. The bedroom window has a 1/2 gap beside it.The drywall in the bedroom is cracked in three or four places.Has anyone ever tried those slab jacking companies?The part sinking has just a footer,the rest of the house has a basment under it.Trying to figure something out,don't know what to do.

I'm no expert but from what i have learn over the last 74 years having worked building houses when was in high school and building one after I retired and owning one here in Oregon where everything shifts I would think that it will most likely have to come down in that part of the house. But get several people from different job types to look it over don't take the word of one outfit. It might cost more to fix than to replace and have to do it over. Those are large cracks that tell it may be beyond repair.
Walt

I've used them but mostly for raising sidewalks and building aprons. The courthouse I used to care for is about 3 blocks off a river we were seeing differential settlement from either improper consolidation of fill during construction or shrinkage of histic soils caused by a drop in the water table (Green Bay is quite a bit below normal right now, most everything in town is built on sawdust). If your mud-jacker or slab jacker can get under the footing they might give you some relief if that's the problem.

You need to have Nolan Ryan take a look at that. LOL.

My daughter's house developed cracks a couple of years before she bought it. Professional company jacked it back into place and stabilized it. It has now been about four years and the cracks have not re-emerged.

I guess it would depend on the price of the slabjacking, wheather I would take Walts advice, or take a chance on lifting it up. It sounds reasonable that the structure has been comprimised by setteling, but rebuilding is very expensive also. Just maybe it would save the existing building! The wife just had slabjacking done to her spine, and it worked great so far. They pushed up a crushed vertibra, with a baloon, to straighten it, and then deflated the baloon, and filled the void with some kind of cement. It took most of the pain away, but its only been 3 wks, so it is still bothersome.

good company can fix it...seen it done alot here in Texas...get references and check work...theres shysters everywhere these days.

(quoted from post at 20:06:53 09/25/12) Our 1800 square foot house was built in 1976.The corner bedroom is settling and the outside wall is cracked by the window.The bricks have a 1/4 inch or more crack down the wall. The bedroom window has a 1/2 gap beside it.The drywall in the bedroom is cracked in three or four places.Has anyone ever tried those slab jacking companies?The part sinking has just a footer,the rest of the house has a basment under it.Trying to figure something out,don't know what to do.

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I don't think mud jacking will solve your problem. Mud jacking is used to raise slabs and flat work. It sounds like you have a conventional foundation with a footing and stem wall that is settling. You could raise the stem wall with hydraulic jacks or screw jacks, back fill the jacks with concrete, then excavate the rest of the footing and back fill with concrete. Most guys who repair foundations will just jack up your house and fill the gap between the mud sill and stem wall with non shrink grout. I don't like this method but the engineers seem to go for it. You might want to try to determine why the footing is settling. If its caused by water, you might have to install a french drain around the outside of your house to stabilize the soil underneath the footing.

Down here is clay soil and it heaves and shrinks terribly. Cracks such as yours are common. Foundation companies drive pilings down into the ground until they stop....bedrock...not hardly, but they finally stop moving. They then attach your house to that and jack it up till fixed. Then a hole is dug, a footing (numerous as required) is poured and on the footing a concrete pier is placed which supports the house and the whole thing is covered back up. I don't do the work but that is the general process. Son does it.

Mark

Have to see how others weigh in...this is only one experience:

But my BIL mudjacked the floor of his machine shop - a few years later, it is sinking again. The ground just is not stable in the area of the building he bought. He has not been happy with it and it cost him a lot when he had the job done.

I do home remodeling for a living and I advise my customers to avoid the house jacking. They can spend tens of thousands of dollars to have this done and it often creates more cracks in the walls and the jacking is seldom permanent. From what you described I could fix the cracks in the walls inside and brick outside for about $350.00. Make sure the house leveling is really necessary.

I expect that the effectiveness would have a lot to do with why it settled. Part of the floor of my shop building settled due to frost under it when poured. If I had it jacked there would be no reason for it to ever settle again. If you are over ground being destabilized by water or something like a buried stump or refuse dump, it would just settle again.

"The part sinking has just a footer,the rest of the house has a basement under it."

There is the crux of your problem.

We have had this situation twice in 2 different houses we owned. Vowed never to buy/build anything that combines 2 different types of support again.
One was original basement/foundation with 2 additions with foundations under them hanging off.
Both of these sloped away from the original foundation. One really badly.
Second home had a large slab under the attached garage and house was on cement pilings. Garage stable, floating on that slab. House sinking on those pilings.

From afar I will have to assume that the ground is not rock solid stable. The mud jack might work for awhile but might come back.

What we did on one house was to use house jacks under a 6"x"6 beam to level that section. Replaced sill in that area. Which was not easy as while outer wall was all one depth, the perpendicular sills had to be wedged and filled under with cement.
We sold house afterwards so I do not know how long it stayed level.

I would try house jacks 1st, then add more/better pilings. See how that holds it. Otherwise
if this is your forever home and $$$ was not a issue I would go for a brand new foundation under entire house.

Pete

Your basement is built on solid ground. Your other footings are built on back fill or ground that is not as solid. This is allowing your house to settle at differant rates. You need to have footings installed that reach down as deep as your basement so the house will work as one unit.

The link will show you many ways of doing this. I can not say what one is best for your location but do know the cable lock system works very well.
Evolution of foundation repair

If you just pump concrete under the footer to jack it up it is still resting on soft or sinking soil.
The way i have designed repairs is to dig a jacking pit under the footer to good solid soil and jack the structure up--then pour a support pier or installed a screw in pile for support. It would have to be determined how often these new supports would have to be spaced. We have used this method also on bridge abutments that were sinking .

Here in Houston we use a structural engineer to design the fix Typically he will design the fix around one or both the below methods.

The expensive way is to bring in a drilling rig that drills 8" holes down to the next level of solid ground, create a bell bottom, add rebar, and concrete then jack against that to get desired elevation.

They also do compression piers. They dig a hole and use a jack to press concrete cylinders into the ground till the house starts to lift. Cheaper and just as acceptable depending on soil composition.

I recently spent 8k on 46 piers to get a house leveled.

You can mud (concrete slurry) jack a flat slab. A slab home with perimeter and interior concrete beams would cost a fortune. That is why they jack the way I mentioned.

We have the same problem around here. According to a local Civil Engineer, the clay soil here "is unsuitable for roadways and dwellings".....how true.

Recently the county put an all weather top on our road...rocks and asphalt to hold them. They brought in tons and tons of sub surface material, graded, packed, watered, etc. over and over.

Finished and it was super. Here it is a year later and it's like a roller coaster. It's a constant fight...drives the highway dept. nuts.

Mark

TexasMark1,

I think it is a permanent problem too, in the industrial park where BIL"s machine shop is. That whole park seems to be built in a low area that we would call "slough ground" if it was on our farm.

I put the piers under my garage floor when I built it because it was on fill.

I am on some of the highest ground around here within 20' (of elevation) of the dividing line (crest) where to the south, water goes south and to the north it goes to the red river.

This is not a national earthquake area, but the plates definitely shift. I have to have a foundation crew out to my house every other year. Having doors close is a luxury. To add to the insult, when it's dry it's dry for months. When in the monsoon season, it's wet for months.

Going over that crest line, N-S, the road is state maintained and over the 35 years I have lived here, they have cut the peaks off the roadway half a dozen times.

But I'm not griping.....I think. On a company trip once, I had to go to NY state and landed in Bingamton, NY and the rocks emanating from the sub surface were at a 20 degree angle and 40' tall, like 50' off the interstate.

Mark

I understand y'all talking about going to solid foundation but here is south Louisiana that is kinda hard. I watched a bridge crew a couple of months ago set a bridge close by. They had 14" x 14" x 72 ft concrete pilings that they set with a 15' pilot hole. was told should take 800 to 850 blows per foot with a pile driver for the pilings, they were getting 3 blows per foot and never hit anything hard to set them on. They left them with only skin tension holding. what is a fellow to do for a home? Just wondering...