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John Dirks Jr
04-30-2009, 08:45 PM
Once soil conditions and drainage issues are handled, what are some ways to repair the cracking and bowing wall?

Ted Menelly
04-30-2009, 09:18 PM
Once soil conditions and drainage issues are handled, what are some ways to repair the cracking and bowing wall?

Not cool at all. That is about the worse crack you could have. How to fix it. Well , it should have been done when they did work outside. There is no fixing that crack other than mortaring the joint which would do about nothing. My belief is that the wall is going to continue to come in and eventually collapse.

I do belive this is about the best example I have seen in some time for an engineer. The wall is simpley just going to cave sooner than later withthe outside pressure constantly pushing on it.

Brandon Whitmore
04-30-2009, 09:43 PM
Try these:

Foundation Movement, Foundation Wall Structural Repair, Carbon Fiber Grid Straps | Emecole, Inc. (http://www.emecole.com/carbon-fiber/grid-straps.html)

Ted Menelly
05-01-2009, 06:34 AM
That crack is beyond mesh. It is seriously leaning inward and ground pressure alone is going to continue to push it in.

That mesh is just for cracks that are not at the point of the wall caving in, in the near future.

Thomas McKay
05-01-2009, 06:41 AM
I have encountered this quite often; have seen some cases where vertical steel reinfourcement has been used successfully. It does require engineering advice and most of all control of ground water at the exterior. The pressure will continue unless the soils is controled. Not good!

Bryce Jeffrey
05-01-2009, 06:50 AM
I had a new poured concrete foundation wall crack. Caused by the bulldozer backfilling the green concrete and running too close to the wall. We excavated the trench, jacked the wall back vertical and installed a buttress knee wall on the interior. That is a horizontal crack and it is serious! Make sure the exterior is properly water proofed before you back fill. By the way that is not a hydrostatic break! Just my opinion.

Jerry Peck
05-01-2009, 07:02 AM
Not sure if some of you guys missed this part or not, but ...

Once soil conditions and drainage issues are handled,.

John as asked that, once those issues are taken care of, and there are no more pressures on that wall to keep pushing it in, ...

what are some ways to repair the cracking and bowing wall?.

Not being a basement person myself, I am wondering the same thing.

I am also wondering if there is no steel in that masonry wall. With the know pressures of the soil, and the known problems with those pressures on basement foundation walls, why ... why ... would one even consider constructing a basement foundation wall of plain masonry or plain concrete (no reinforcing in the wall)?

Is it simply "cost"? A little as that cost is a related to the entire cost of the structure, and its great influence on the structure, given the cost of correcting it later (having to do excavation around the structure)?

Surely builders are not THAT STUPID and tight ... are they? :rolleyes:

John Dirks Jr
05-01-2009, 07:10 AM
Here's another wall from the same house.

The wall is leaning in and the beam is displacing the top coarse and deforming the sill and the rim. There are major water control issues with this property.

You can believe I called for a PE and a foundation specialist. Let me go back and double check before I click send. I think I'll add the word "strongly" in front of the word "recommend".

Thomas McKay
05-01-2009, 07:17 AM
Not being a basement person ether, afterall its like trying to make a swimming pool a livable space, we do need to consider the enouous pressure the soil has especially on the up hill side of the foundation, it is always better to use reinfourced concrete but for minimum codes and cost that dosen't happen to often. I think in some cases even when rebar and filled block are used the fource of the soil wins out and can cause the horizontal cracks we inspect. I have seen correction as easy as adding a curtain drain at the up side foundation wall exterior. Control of water from the inside is a joke and only cosmetic.

Thomas McKay
05-01-2009, 07:21 AM
That really looks bad John, is the foundation built on a hill and is it slipping down hill, is there lots of sand in the soil?

Jerry Peck
05-01-2009, 07:23 AM
I think I'll add the word "strongly" in front of the word "recommend".

John,

I can never understand why home inspectors' do not simply state what is needed, i.e., in stead of "recommend" or "strongly recommend" just state the facts "structural engineer NEEDS TO DESIGN APPROPRIATE REPAIRS to the moving and failing foundation walls".

Just state that a structural engineer is NEEDED, and what they are NEEDED FOR ... to design appropriate repairs for ...

You can "recommend" the house be torn down, however, there is a way one can keep that from happening - a structural engineer is "NEEDED".

I've never understood the hesitancy of home inspectors to use the word "needed".

As in 'it NEEDS a new roof', or even a more strongly worded version of that 'it NEEDED a new roof 5 years ago, NOW IT NEEDS A NEW ROOF AND ROOF SHEATHING', etc., :) .

Jeannot Cote
05-01-2009, 07:27 AM
I often see crack like this, in my area there cause by frost pushing on the wall especally on the driveway side. To repair they completly redo the wall 9000$ plus

Jeannot

Jerry Peck
05-01-2009, 07:32 AM
I think in some cases even when rebar and filled block are used the fource of the soil wins out and can cause the horizontal cracks we inspect.

"Cracking" when there is reinforcement in the wall is not a big deal, the wall, with sufficient reinforcement in it per the accepted designs, is not going to "fail" in the wall that block wall without reinforcement in it is going to fail.

The reinforcement will keep the wall together, albeit slightly bowed, as the the steel will become in tension (its purpose) and hold the wall together. At that point, you then need to be concerned about the pressures pushing the wall in at the bottom, except that when steel is in the wall it will be (should be) tied to steel in the footing, which will prevent (greatly reduce the risk of) that from happening. You are then left with the pressures against the top of the wall, which are much reduced, and with a bond beam or tie beam around the perimeter of the wall with steel tied to the wall steel and to the footing steel, that bond beam or tie beam is not going to move much either.

It just seems to me to be a very foolish "money saving" to not use reinforcing in the footings, foundation walls, and bond beam, etc.

Save the money someplace else, someplace which will not allow or cause the structure to fail, someplace which will be accessible and allow for much less expensive repairs. But, to answer my question on my earlier post, yes, builders are that STUPID AND CHEAP ... unfortunately.

Steve Frederickson
05-01-2009, 08:16 AM
John,

I'm not sure what you mean by "once soil conditions and drainage issues are handled..." Did you completely remove the soil on the exterior? If not, then there is still pressure on the wall from the soil. You may have reduced the pressure by addressing drainage, but if the wall is already failing, any pressure will likely make it eventually collapse. Even if you've removed all of the retained soil, there is still wind/snow to consider.

I recommend an engineered solution. Often, pilasters can be installed on the inside to brace the wall or try this: PowerBrace.net - Foundation Wall Bracing Systems (http://www.powerbrace.net/)

Jerry Peck
05-01-2009, 09:02 AM
I recommend an engineered solution. Often, pilasters can be installed on the inside to brace the wall or try this: PowerBrace.net - Foundation Wall Bracing Systems (http://www.powerbrace.net/)

Steve,

I would not be concerned as much about the cost of feeding that elephant as I would be about cleaning up after it ... :eek:

:D

Stuart Brooks
05-01-2009, 10:30 AM
The repair I've seen used 4" steel H-beams spaced at 3-feet along the wall, set into concrete and bolted to the floor joists above the basement.

Ted Menelly
05-01-2009, 10:43 AM
Again

An ebgineer is required. You can put all the steel you want inside but the area behind that wall was not dug up and pressure relieved.

On the surface the soil conditions kmay have been improved and the drainage as well but you need to relieve the pressure at the exterior.

You can brace, patch cover over, ignore or what ever you want but in the case of a basement wall that has that much pressure pushing in against the wall the pressure has to be relieved. At the same time that they dig out on the other side of the wall they can implement proper water barrier as well. The wall has been cracked. Patch the inside, water still gets inside the block from the exterior. There is no other choice but to relieve the pressure on the exterior. Apply proper water barrier. Add a drain at the bottom of the wall. Add proper soil and proper drainage at the top of the wall.

Obviously all this will be put forth by an engineer but if the engineer just gives a fix on the inside tell your clients to ignore the fool and find someone else and give the money to the reall fixer engineer and not to the firtst fool that just gives a fix to the interior.

If the seller is fixing it I guarantee you they are going with an inside fix which is no fix at all.

John Dirks Jr
05-01-2009, 06:45 PM
John,

I can never understand why home inspectors' do not simply state what is needed, i.e., in stead of "recommend" or "strongly recommend" just state the facts "structural engineer NEEDS TO DESIGN APPROPRIATE REPAIRS to the moving and failing foundation walls".

Just state that a structural engineer is NEEDED, and what they are NEEDED FOR ... to design appropriate repairs for ...

You can "recommend" the house be torn down, however, there is a way one can keep that from happening - a structural engineer is "NEEDED".

I've never understood the hesitancy of home inspectors to use the word "needed".

As in 'it NEEDS a new roof', or even a more strongly worded version of that 'it NEEDED a new roof 5 years ago, NOW IT NEEDS A NEW ROOF AND ROOF SHEATHING', etc., :) .

I usually say, "hire a (insert choice of profession) and have them fix it.

John Dirks Jr
05-01-2009, 06:48 PM
That really looks bad John, is the foundation built on a hill and is it slipping down hill, is there lots of sand in the soil?

Mainly poor grading and expansive clay soils.

John Dirks Jr
05-01-2009, 06:52 PM
John,

I'm not sure what you mean by "once soil conditions and drainage issues are handled..." Did you completely remove the soil on the exterior? If not, then there is still pressure on the wall from the soil. You may have reduced the pressure by addressing drainage, but if the wall is already failing, any pressure will likely make it eventually collapse. Even if you've removed all of the retained soil, there is still wind/snow to consider.

I recommend an engineered solution. Often, pilasters can be installed on the inside to brace the wall or try this: PowerBrace.net - Foundation Wall Bracing Systems (http://www.powerbrace.net/)

I didn't do any work and I'm not sure what has been done in the past. I had the idea of what caused the crack. After correcting the cause, I was inquiring on how to address the resulting crack. I'm just looking for general knowledge so I can add data to my brain.

Steve Frederickson
05-02-2009, 07:46 AM
Ok. I thought you were saying that the problems had already been addressed. While addressing drainage problems and problems with the expansive clay will help, that wall has already failed. Unless you want to rebuild it with a cast-in-place or reinforced masonry wall, the next best solution would be to brace it on the interior with engineered pilasters, steel columns or with a proprietary product such as Powerbrace.

If something isn't done, it WILL eventually collapse, and the collapse will be sudden, probably happening during a heavy rain.

Adding some shoring under the floor framing adjacent to the wall is probably a good idea until the wall is repaired, but an engineer should be contacted before doing anything. In some cases, adding shoring can actually make the problem worse, because the weight of the floor on top of the wall can actually be helping, by bracing the top of the wall.

If shoring is installed, it should be installed slightly loose with some give, so that you're not relieving the weight of the floor from the foundation. The only purpose of the shoring would be to prevent the floor from collapsing in the event that the foundation collapses.

I've seen many foundation collapses (both stone and block), and I've never seen the floor above also collapse. There might be some slight movement and cracking, but usually what happens is a moderately sized section (maybe 10') of the foundation collapses and the floor framing above is able to span the opening in the foundation. The floor is then shored and the foundation is then repaired, but I still recommend shoring the floor before the foundation collapses, as a precaution.

I hope this helps.

Sal Castro
05-03-2009, 02:01 PM
Steve
You are right. This foundation collapse I inspected a few weeks ago at a foreclosed home did not seem to have much effect on the joists directly over it, and the floor above did not even seem to slope much. I have seen more sloping in floors with foundation settlement and no collapse.

Just the same, I could not wait to get out of there as the access stairwell was adjacent to the problem wall. The buyer/speculator ran quickly too.

Sal Castro

Steve Frederickson
05-03-2009, 02:59 PM
A little too late for bracing to help on that one ;)

Eric Barker
05-03-2009, 06:36 PM
Stuart,

I've never found any qualified authority who found much use for the vertical beams on block foundation. The problem is that the blocks on either side of the beams continue to push in. The beam installation will have much better success with poured concrete foundations.

Steven Turetsky
05-04-2009, 06:45 PM
Hi

I started reading down, and finally jumped to the bottom Some of my response may be redundant, I'm sorry.

The way I see it, there are two separate issues.

First off, it was stated that drainage and soil issues have be resolved. IWe can't see everything that is a factor, but by just looking at the picture, well, I've seen walls that were alot worse, stand for quite a while, most are still standing. If the wall is stabilized, and the increased pressure of the water is relieved, I would just keep an eye on it before I started tearing it down.

As far as the repair. Especially since the inside is so accessible, I would use a product called "Hydrophobic Polyurethane." I've seen this stuff stop running water before my eyes. A day or two later, after it's cured, you cut off the excess and paint the wall. You will never see it.

Of, course, whomever applies it should be carefull they don't blow out the wall. It may make sense to brace the wall until its cured.