Mud jacking (concrete slabs)

[scott_l]

I have a split entry house with a large cement patio out back (there is about a 1” gap between the slab and my foundation). The patio is sectioned off into 4 equal parts via troweled in expansion joints. All the expansion joints have cracked but the slab still looks good and is in good condition. But the two slabs next to the house have shifted/moved and when it rains (or snow melts) I get a large puddle next to my foundation. Overall size of the patio is about 16’x20’ so I really don’t want to bust the entire patio out and re poor it.
I was thinking of having the two slabs next to the house mud jacked (they drill a couple holes in the concrete and then force some stuff under the slab to raise it) so the water runs away from the house, but I have read different reviews/info online.

Anyone have this done before, any problems, suggestions?

 

[thebreeze]

Its not the best fix, but is the most economical. Different companies use different methods. The main issue with it to me is you end up with a slab that is not evenly supported once they pump the "columns" of "mud" under the low corners. The slab can be more prone to additional cracking in areas other that the expansion/control joint, but you will no longer have water running towards the foundation.

It is a good option if you do not want to pay to have it cut put and re-poured.

The worst case scenario, is you end up cutting it out and having it repaired years down the road if the slab cracks too much for your liking.

 

[rmk4ever]

Well I have removed alot of it, I mean alot. It seems to me that all I have tore out still remains in a liquid like state, good for raising & fixing problem area's, however not a very good subgrade base. Your problem goes back to the "prep" of said patio. Im sure it was layed the same yr the house was done, or the following spring. The backfill on the "overdig" part of foundation was not setteled enough. Now it get's washed away everytime theres water going down there. Do what you will, but know this it's just a BAND-AID & will require more "fixes" as the seasons pass by. On a lighter note times are tuff for the trades in the cities & surrounding sub's, so good deals are to be had with a little shopping of course. You see alot of mudjacking around the maplegrove & plymouth area's, both res.& comm. I'm a concrete contractor & that's my exp with mudjacking.
Also I find alot of "stuff" in the mudjacking mud, newspapers, gloves, cardboard, rags, t-shirts even stryofoam... cheap fillers!

 

[G]

It was likely done wrong to begin with. There should have been some kind of solid support built up from the footing to support the slab next to the house. I would not mudjack it. At best it would only be temporary and at worst it could screw up the house foundation. The foundation could move before the slab. Murphy's law.

 

[jomama45]

I'm a concrete contractor as well, and although I think the best long term solution will be to replace the whole slab eventually, I see no reason not to look into mud jacking if it's going to cost a fraction of the cost. I personally work with a great MJ'er, and have no reservations in giving his name out if I think it will give the customer a good job for a better value than I can offer them. He returns the favor as well, when he feels the concrete is beyond feasible repair.

 

[scott_l]

I am pretty sure the issue arose because the ground settled (like mentioned above). It just goes with the house (many stupid problems).

I have also done some reading on line and found another product/service where they force a sand/water mixture under the slab (sounds like the same process as mud jacking but different material). Any better?

I will admit I am trying to take the easy/cheaper way out, we have already been in this house longer then we planned when we purchased it so we don't want to dump a bunch of money into the house. But at the same time don't know if we will be able so sell with in the next 3-5 years so don't want to dump money into it and not have the problem solved.

Hence I am asking for your thoughts

thanks for the replies so far.

rmk4ever I have to laugh as I am not far from the areas you mentioned, I live in Blaine

I should also add I have not had any one come out and give me bids yet, figured I would try and get some info before I got bids so I can try and act like I know what I am talking about

 

[booondocker]

Unless and until you correct the support under the edge next to the house, it will just continue to walk away.

While mud jacking is certainly one of your options, it doesn't do a very good job of correcting the real problem mentioned above about proper support under the cement next to the house. Now that there is a place for water to track to and keep going there, not only can this lead to freeze thaw issues, along your foundation, it can and will continue to wash away the soil providing less and less support until even more cement cracks and walks.

I would hunt and find a cement man who can come in there and cut about 15-24 inches of the cement slab off the edge that used to be butted to the house. That isn't much cement. Then once the cement is removed there needs to be some serious compacting of the soil next to the house. For this reason, I would wait until the dry months come...july and august likely and then compact the heck out of that dirt next to the house adding as much as you can and making sure it has been very well compacted.

Then re pour the concrete in the gap and seal it up. This will have long term results you will be happy with and unless the other slabs are uneven and all over the place, will be quite inexpensive with regard to concrete costs. You can take a week or two to compact the soil yourself...so tell the contractor to give you some time between the pours to do that.

Once this is done, you stop the soil from eroding away from the foundation, and you get a good slope away from the house so water doesn't pond there.

 

[todds]

I'm with jomama45. Give mud jacking a try to correct your pitch problems. It's much less expensive than a complete tear-out. Don't just jack the two adjacent to the house though. Jack the whole slab to the correct pitch.

For your gap between the slab and the house foundation, get some poly backer rod and a good jointer sealer like Sika 1A. The 1A is a single-component material which will be easier to work with for inexperienced person. If you want to go really high-tech, try Sika 2C-SL. It's a two-part, self-leveling epoxy material that we use in wastewater treatment plant applications to seal tanks. Good stuff.

If you can't pitch your slab with mud jacking, you can always tear it out and rebuild it. You can use the same joint sealer with the new installation

 

[mikeh906]

Do you have gutters? It might be the same cost to cut out a section, put in a new grade and repour to move the water away. A couple of feet out, I have used mud jacking before [1993] by our pool.[16 ft]. It really depends on how much of a lift you need. It solved the problem, similar to yours, and never had any other issues. Sealed everything, 2x. Wish I had sealed it that well to start with. It was not my first build and I was in the concrete biz at the time, so it is something that happens.

 

[vw56german]

Mud jacking is a viable option. The company that does it should drill enough holes so they inject material to fully support the lifting of the slab leaving no void areas. I had a home where the poured front step had settled enough to pull away more than 2" from the foundation, and sink about 5" to one side. This caused the brick butrusses to crack and come apart. I had the steps and walkway jacked until they were properly sloped and rebuilt the brick work on the sides. I have since sold the house but live in the area. Some 20+ years later the steps and brick work are still properly in place and look good. Each situation is different, but my $.02 is that mudjacking is an option. A good company should be able to evaluate the job and give you reasons why it will or will not be a success.

 

[zrgrl]

I have also done some reading on line and found another product/service where they force a sand/water mixture under the slab (sounds like the same process as mud jacking but different material). Any better?

The sand/water mixture is the same as 'mud jacking'. My boyfriend owns his own business in 'mud jacking' so I get educated all the time about it But if you are looking into doing this, research your companies and make sure you pick a company with the right materials, such as sand, gravel, ash, portland and water. And just remember if the cause is something like a leaking eve spout it will only be a matter of time before the concrete sinks again. Hope this helps.

 

[ibendwire]

I actually did mud jacking for ten years while in school and I can say that it does work well. If done correctly it can last a long time. Well worth it if your cement is in good condition. We used either fly ash or crushed limestone for our mixture. Obviously it must be done correctly. The holes must be drilled in the proper locations as well as the placement of the holes. Also the mixture must be at the correct consistency in order to have the material flow underneath the concrete and not leave large voids. the material is quite stable however if the ground underneath continues to settle the cement will still drop.

 

[petro1]

My parents had part of their driveway mud jacked. It was the three (14x14)pads in front of each garage door. They were all about 2"-2.5" below the grade of the garage floor. They driveway was originally poured in 1989, and they had this done about 4 years ago, none of them have moved or cracked since. They were happy with the outcome/price. We also have full size pickup trucks parked on the sections daily, so I think its strong.

 

[xcr440]

I've seen them do this on the interstate. 35E in Eagan, MN had a real bad spot where the soil underneath must have settled more than they expected (Or the compactor just didn't get it packed in that one spot) and they corrected that spot on the freeway without cutting and repouring.

Anyone familiar with this spot between Diffly Road and Pilot Knob would remember it well.

 

[t_man]

Worked with it a lot

I'm in corporate real estate and have had concrete lifting done many dozens of times over the years. You've gotten good advice up above, so I'll just add a little and summarize.

Concrete lifting can be very effective as long as the root cause of the concrete settling has been addressed.

If the concrete is settling because of poor drainage, a broken pipe, poor soil compaction where the soil is still settling, etc. then the concrete lifting will be just a temporary fix. The concrete will settle again due to the root cause.

If the root cause has been addressed and the underlying soil is stable, then concrete lifting is great. I can't recall a single failure of a concrete lift in those situations.

Sounds like you have a reasonably good chance that the cause is original settlement at the foundation and potentially some water infiltration because the slab is now sloped toward the foundation. If so, there's a good chance concrete lifting will work so I'd give it a shot. As noted above, make sure you've got good gutters, good drainage, etc.