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geeman
Dec 26, 2008, 11:25 AM
My interior concrete basement walls have some bowed areas and a small portion broken off, how do I repair this.

21boat
Dec 26, 2008, 12:06 PM
I'm A mason please describe "bowed" areas better.
"Interior basement wall" Dirt on the out side or no dirt?
What section of wall?
Total area bowed?
Approx age of wall?
Crack length and size If any?
Height of bow from floor to ceiling at its most center bow.
Can you Plumb down and give deflection of bow.
What broke off "block face or what size "
How is the outside grade on the wall and the downspouts/gutters set up?
Did the bow just show up or has it been over time?
This is a could be a serious thing and my answer you might not want to hear
Signed 21 boat

geeman
Jan 11, 2009, 02:14 PM
Sorry it took so long to get back to this. I will get the answers together and post them this week.

ballengerb1
Jan 11, 2009, 05:58 PM
Geeman, we will wait for your details but I can tell you there isn't much in the line of repairing a bowed concrete basement wall. It likely needs to be totally torn out and replaced. The wall once was straight, we assume, and something applied enough pressure to bow it, can't be fixed to any where near as strong as it once was. Tell us more.

Rivethead
Jan 12, 2009, 04:20 AM
We had a width wall that bowed in and cracked. Had 4 basement repair companies look at it. Some wanted to put "straps" on it.
Another wanted to ad steel wall beams. Then there was the one that said the foundation needed piers added (bull! )

I didn't want something added that would scream repaired wall. Had a company called A-1 Concrete (think they are a franchise) come in and work on it.

They dug down to the footer along the side of the house. Slid wood beams in through the basement windows and jacked those against the wall with hydraulic jacks. With the wall pushed back in place they drilled 3 inch holes in the exterior top block about every 3 feet and pumped the wall full of slurry concrete. Added a second drain line to the outside, etc. All is well - may be an option for you.

21boat
Jan 13, 2009, 01:46 AM
The best option for your wall is what I started to do back in 1984 as a mason/crete contractor. There was a new 2 story house that someone else built the wall cracked and bowed in. The way this happened when the exacter backfilled the new foundation he pushed in a big rock that hit abut midway in the full in ground basement wall and cracked it. To try and remedy it they pushed it back and popped some top block openings and ran some rebar down in some cores to the bottom of the wall and poured slurry concrete. Well on this one two years later it pooped and the wall cracked and bulged in. I was hired by the insurance company to fix it and that's part of what we do. I dug the outside 52' full basement wall. Inside I used a 2x8 top and 2x12 bottom plate doubled up.The temp wall was set 1 foot from outside of the original wall and 2x8 16 oc . This made a cantilever for the house to sit on the studs were slightly pressured in to get compression by compaction to pre stress the load weight in transfer. I removed the whole block wall. I added 3 new offset of concrete footers to original footers and tie in rebar. Now when I laid the straight wall I built the added "pile asters to new wall and capped the below grade. The it was parge pitch and perforated pipe in 2b clean stone and backfill. pull temp wall out.
I personally don't agree with rivetheads A-1 concrete company with their way of repairing the wall. I'm assuming its an 8 or 10 inch block wall depending on the age the structure. 1. When you try to save a cracked bowed wall and push it back that wall area is essentially shot. The drilling of the holes in the block to me was a bad attempt of pouring an underated "pile aster" to pin it. Also I didn't see any mention of rebar in the little holes of the block wall. Even so a 10 inch 2 core block holes is 5x6 to pour crete into That mini "pile aster" is not very strong for longegetive. remember the distance between the mini pile asters was moved twice in fracture. Once when it was bowed and once when it was jacked back. So based on simple science the space between 3 foot slurries is just a filler with no "shear" properties left. One real basci thing about concrete and block is its fantastic for "compression" but lousy for "shear" side ways pressure. I E rebar in the crete. So bascialyy the only thing keeping rivetheads wall in tact is Compression from the house weight but that walls over all shear properties are very much dimnisshed betaween the mini pile aster poured My point on shear is look at how many retaining walls fall over or bow. Of course no house on it but still they are tough to build and must be overbuilt to compensate for the shear part. Since the 80s I have jacked a lot of big old tobacco barns and earthbank garages and even move a house. I run into a couple every few years or so. Nothing failed yet since 1985.
So Geeman bascilay what I wrote above is really the only way to repair a bowed block/ stone wall to begin with. Now if your wall was an 8"wall like they did a lot on houses in the 60s back for in ground walls the it was an under rated wall to begin with and I wonder what Rivethead wall was in width. When you replace a wall that's 8 wide is easy to do it back in 10s as long as the inside wall footer is wide enough. The house plate anchor bolts connection is easy to a point.

Rivethead
Jan 13, 2009, 09:58 PM
Geeman - what I was trying to give you was what to watch out for when you start getting some estimates. Not the entire construction process in detail - that's what the contractor and the consulting structural engineer were for. Our home was built in 90 with 10 inch block.

The work A1 completed did actually involve driving rebar down into the holes - the wall pushed back the 3/4 inches it had bowed in the center - and any minor evidence of the interior mortar line cracks sealed. The slurry they pumped into the wall was fiberglass reinforced. The wall was re insulated and waterproofed. An additional drain line was also added. The work came with a transferable lifetime warranty. It's never budged or leaked since and I can't ask any more than that.

The structural engineer report by the way will be money well spent. It will be a very small portion of what your going to spend on this work - trust me on that. Beyond the repair advice they will help you correct the problems that caused it in the first place. Just watch what your doing in this process - don't bother getting estimates from anyone that does interior strapping on the walls. There are a lot of companies hoping to take advantage of your concern.

21boat
Jan 16, 2009, 03:45 AM
Not the entire construction process in detail - that's what the contractor and the consulting structural engineer were for. Our home was built in 90 with 10 inch block.

The detail I gave was done by the Lic / insured G.C. Contractor Me and Also by/with the Lic Engineer. I just detailed an application that was engineered that seems to work best. You can get three engineers with three different ways of doing it and yet the engineers don't agree with each other imagine that Its not to say that all three wouldn't work, But I had engineered specks not work before. Not everything needs engineered. In standard building practice we know a 6" double plate wall can carry with ease a 2 story house with a 2' cantilever. The only equation is the concrete floor on temp 2x8 studded wall spreading the load out to temp. carry the weight. Sorry I understand the concerns here but If we in the field had to call an engineer out for bracing we all go broke. But if not sure call one.

homeowner190
Oct 31, 2009, 12:18 PM
Rivethead - do you remember the approximate cost of the work A1 did for you on that foudation wall including the drain, warranty, etc? Thanks.