Foundation Repair Methods Compared: What Each One Does and Does Not Do
There is no single foundation repair: the methods fix different problems, and the wrong one can leave the cause in place. Start by finding the cause, then match the method to it. This page explains what the main options are for and the limits the engineering sources themselves state.
Start with the cause, then the method
The ASCE Texas Section guidelines for evaluating residential foundations describe a method: observe, analyze data, form hypotheses, test them, then reach conclusions. They separate structural integrity (cracks, tilt of posts or piers, material deterioration) from performance (whether the house works as intended: cracked walls, racked door frames, deflected framing).[1] A repair should follow from that, not precede it. Moving water away, stopping a leak or managing a tree can matter more than anything done to the concrete.
The main options
| Method | What it does | Cautions from the sources |
|---|---|---|
| Non-structural measures: drainage, grading, gutters, watering program, tree management, moisture barriers | Reduces the moisture swings or water loading that move the soil. | The ASCE Texas Section lists these as common first steps.[1] Avoid excessive watering and do not run downspouts into perforated subsurface drains.[1] |
| Underpinning with piers | Adds support beneath the foundation, extending to deeper or more stable soil, and can raise settled areas. | Underpinning generally does not improve non-underpinned areas, and elevation adjustment is unlikely to produce a fully level foundation.[1] See Piers and underpinning. |
| Slabjacking (mudjacking or foam) | Injects grout or polymer foam under a slab on ground to raise it or fill voids. | Levels the slab but does not correct underlying poor soil conditions; continuing settlement may need repeat treatment.[2] See Slabjacking, mudjacking and foam. |
| Crack repair (epoxy injection, dry-packing, routing and sealing) | Seals or bonds cracks, mainly in concrete walls. | Does not stop whatever caused the crack; the concrete industry advises professional advice for cracks that keep widening and checking drainage first for leaking cracks.[3] |
| Post-tension tendon stressing | Re-stresses tendons in a post-tensioned slab. | Listed among slab remedies by ASCE Texas Section; specialized work that should follow an engineer's evaluation.[1] |
| Partial demolition and reconstruction | Removes and rebuilds damaged slab or foundation sections. | Listed by ASCE Texas Section among slab remedies; considered for severe distress.[1] |
| Wall stabilization for bowed basement walls | Braces or reinforces a wall (steel or carbon fiber strips, anchors) or rebuilds it. | We found no independent comparison of systems. The cause (usually water or soil pressure) must also be addressed. See Bowed basement walls. |
| Pier and beam repair | Shimming, framing repair, added or replaced supports, restoring void space, crawl space moisture control. | ASCE Texas Section lists these as common remedies.[1] See Pier and beam foundation repair. |
Limits the engineers themselves state
The ASCE Texas Section guidelines make several cautions explicit, and they apply well beyond Texas:
- Remedial measures cannot achieve perfection, and their limits should be stated.
- Underpinning generally does not improve non-underpinned areas.
- Elevation adjustment is unlikely to produce a fully level foundation.
- Grouting should not be placed beneath underpinned areas if soil swelling could damage the structure.
- Test water, sewer and gas lines after lifting, and repair leaks.
- Take floor elevation measurements after remediation, and keep a record.
(All from the ASCE Texas Section guidelines.[1]) A contractor who promises a perfectly level house is promising something the engineering literature says is unlikely. See questions to ask a foundation contractor.
Who decides the method?
There are two common paths. In one, an independent licensed engineer evaluates the house and writes a repair specification that contractors bid on. In the other, a repair company inspects the house and proposes its own solution. The first separates diagnosis from sales; the second is faster and often free but the person recommending the repair profits from it. See do you need a structural engineer?
After the repair
- Ask for a post-repair floor elevation survey and keep it.
- Continue to monitor cracks and doors; some cosmetic repair is normally a separate step.
- Fix the cause: drainage, leaks, trees. A repair does not remove the soil or water that caused the movement.
Common questions
What is the most common foundation repair?
That depends on the foundation type. For slabs, ASCE Texas Section lists underpinning, grouting or mudjacking, crack injection and tendon stressing; for pier and beam, shimming, framing repairs, added supports and moisture control; and for any house, drainage and moisture management.[1]
Does foundation repair make a house perfectly level?
No. The ASCE Texas Section guidelines state elevation adjustment is unlikely to produce a fully level foundation and that remedial measures cannot achieve perfection.[1]
Do I need to fix drainage before foundation repair?
Usually it should be part of it. Without addressing the water, the cause of movement remains. Engineers list drainage, grading and watering programs among common measures.[1]
Is crack injection a structural repair?
Epoxy injection can bond a crack, but the concrete industry's guidance is to find the cause first and get professional advice for active cracks.[3]
Related guides
Sources
Figures and claims marked with a number come from these sources. Dates are the publication or last-update dates shown by the publisher, where one was shown. Older sources are flagged in the text.
- Guidelines for the Evaluation and Repair of Residential Foundations, Version 1. Texas Section, American Society of Civil Engineers; adopted October 3, 2002, effective January 1, 2003.Written for Texas conditions and by its own terms not a standard of care. Widely used as a reference for slab and pier-and-beam evaluation. Published in 2002.
- RAP Bulletin 11: Slabjacking (ACI RAP-11). American Concrete Institute, Committee E706; primary author Fred R. Goodwin; copyright 2010.Covers slabs on ground (floors, pavements), not house foundations as a whole.
- CIP 7: Cracks in Residential Basement Walls. National Ready Mixed Concrete Association (NRMCA); copyright years 1979, 2000 and 2014 shown, with 2014 the most recent.Industry trade association for concrete producers. Focuses on poured-concrete basement walls.