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Undermined footer solution

Kurt99's picture

A condo complex I work for has many places where the footer under the crawlspace walls have been undermined. These are 40 year old buildings with concrete block walls. I know that the first step is solve the water problems that cause the problem in the first place. This either has been addressed or is being addressed. 

We are a reasonable method to add support to prevent the walls from cracking, settling, or collapsing. My thought is to pour/shovel/force concrete into the space under the footing. Other than being a nasty job, are there problems that I haven't thought of or any better ideas.

You can certainly pour, scoop (post #215181, reply #1 of 3)

You can certainly pour, scoop or throw concrete under there but it's a lot of work, look sloppy and will require a lot of work  to make sure it actually provides support. A faster, easier, stronger and less expensive way is to hire a gunite contractor to spray the voids with gunite. Put a simple plywood form on the inside to contain the gunite and have at it. The spray will fill every void, can be finished quicky and will provide the structure you need. 

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

Yeah, think you need some (post #215181, reply #2 of 3)

Yeah, think you need some sort of a pumped solution.  Around here you'd probably look for a "mud-jacking" contractor, though the specific technology used would depend on the particulars.


Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

I had a large section of slab (post #215181, reply #3 of 3)

I had a large section of slab on grade where a busted watermain washed away big sections of the undelying fill. We cored drilled holes every 4ft on center over a 1200 sqft area and poured in lightweght concrete fill until it perculated up through an adjacent hole.

Some of the sprayfoam insulators have rigs that can do slab jacking by injecting the closed cell insulation through holes in a slab so you may be able to do that to support your footing.