# Repair Methods guides

> How each foundation repair method works: push and helical piers, mudjacking, foam, carbon fibre and wall anchors. Independent.

Canonical: https://foundationrepairlab.com/repairs/

Last updated: 2026-11-08

## Repair methods, and when each is specified

Foundation repair is not one trade. It is a set of methods that solve different failures: a settled footing needs a pier, a settled slab needs lifting, a bowing wall needs restraint, and a wet crawl space needs drainage. The most common expensive mistake is buying wall anchors for a footing problem, or slab lifting for a structural settle.

 |
 | Method | What it does | Specified for | Limit

 | Push piers | Steel shafts driven to bearing strata, bracket under the footing | Settled footings carrying structure | Needs exterior access; not for slab-only settlement

 | Helical piers | Screwed shafts with helical plates | Lighter loads, unstable or sandy soil, tie-backs | Lower capacity per shaft than push piers

 | Mudjacking | Slurry injected under a slab to fill voids and lift | Settled driveways, garage floors, patios | Heavy; may re-settle; not for structural footings

 | Polyurethane foam | Expanding resin injected under a slab | Slab, pool deck, interior floor lifting | Higher cost per sq ft; limited lift height

 | Carbon fibre straps | Epoxy-bonded straps across a wall crack | Cracked, lightly bowing block walls | Does not push a wall back; cosmetic crack remains

 | Wall anchors | Plates in the soil tied to wall brackets | Bowing walls, with outside access | Excavation; not for slabs

 | Slab lifting | Foam or slurry under an interior slab | Uneven floors, hollow spots | Does not fix the soil that caused it

## Piers: how the choice is made

A push pier is driven down until it reaches bedrock or a stratum with enough capacity, then the weight of the house is transferred onto it. A helical pier is screwed in with a torque motor; the installation torque correlates with capacity, which is why the installer records it. Push piers generally carry more per shaft and are the default for a settled exterior footing on a house with a basement.

The number of piers is an engineering calculation, not a sales decision. A typical rule of thumb is one pier per 6–10 feet of affected wall, plus one at each corner of the settled area. A quote that lists "10 piers" without a plan showing where they go is a price, not a design.

## Mudjacking and foam: lifting slabs, not footings

Both methods inject material through small holes in a slab. Mudjacking uses a cementitious slurry and is cheaper per square foot; polyurethane foam is lighter, cures in minutes and can be used where the slab is thin or the subgrade is unstable. Neither addresses the reason the soil moved, so both are maintenance rather than structural repair.

Where a slab is tied to a footing, lifting it without addressing the footing can crack the connection. That is why an engineer will sometimes specify piers first, then slab lifting — not the other way round.

## Walls: restraint versus replacement

A horizontal crack in a block wall with slight bowing is a candidate for carbon fibre or anchors. A wall that has moved more than about 2 inches, or is bulging at mid-height, usually needs anchors with excavation and may need rebuilding. Carbon fibre stops movement but does not straighten the wall; any contractor promising a straight wall from straps alone is overselling.

The [problems hub](/problems/) maps symptoms to tests, the [cost hub](/cost/) carries unit prices, and the [foundation types hub](/types/) explains which failure belongs to which construction type.

### Which is better, piers or mudjacking?

They solve different failures. Piers transfer structural load to bearing strata; mudjacking lifts a slab that has settled into a void. If the house structure is moving, piers; if a driveway or garage floor has dropped, lifting.

### Do I need an engineer?

For structural work, yes — a stamped letter is what a permit office and a warranty claim will ask for. It costs $400–$1,500 and is cheap insurance against a $20,000 mistake.

### How long does foundation repair last?

A properly designed pier system is intended to be permanent, and most carry a transferable lifetime warranty. Slab lifting and mudjacking are maintenance items that may need repeating in 5–15 years.

## Guides in Repair Methods

- [A Best Foundation Repair: What Good Work Looks Like](https://foundationrepairlab.com/a-best-foundation-repair/)
- [How Basement Waterproofing Works: Exterior vs Interior](https://foundationrepairlab.com/basement-waterproofing-how-it-works/)
- [Basement Waterproofing Methods Explained](https://foundationrepairlab.com/basement-waterproofing-methods/)
- [Carbon Fibre vs Steel Straps for Foundation Walls](https://foundationrepairlab.com/carbon-fiber-vs-steel-straps/)
- [How Carbon Fibre Straps Work on a Bowing Wall](https://foundationrepairlab.com/carbon-fibre-straps-how-it-works/)
- [Commercial foundation repair](https://foundationrepairlab.com/commercial-foundation-repair/)
- [Concrete Foundation Repair: Cracks, Spalling, and Piers](https://foundationrepairlab.com/concrete-foundation-repair/)
- [Crack Injection: Epoxy vs Polyurethane for Foundation.](https://foundationrepairlab.com/crack-injection-epoxy-vs-polyurethane/)
- [How Crack Injection Works: Ports, Resin, Pressure](https://foundationrepairlab.com/crack-injection-how-it-works/)
- [Crawl Space Dehumidifier Sizing for Moisture Control](https://foundationrepairlab.com/crawl-space-dehumidifier/)
- [How Crawl Space Encapsulation Works](https://foundationrepairlab.com/crawl-space-encapsulation-how-it-works/)
- [Crawl Space Vapour Barrier: Spec and Cost](https://foundationrepairlab.com/crawl-space-vapor-barrier/)
- [Do It Yourself Foundation Repair: What Is Safe](https://foundationrepairlab.com/do-it-yourself-foundation-repair/)
- [Drainage Repair Around a Foundation: Costs and Methods](https://foundationrepairlab.com/drainage-repair-around-foundation/)
- [Foundation Grouting: Compaction and Permeation Explained](https://foundationrepairlab.com/foundation-grouting/)
- [Foundation Leak Repair: Causes, Methods, and Costs](https://foundationrepairlab.com/foundation-leak-repair/)
- [Foundation Repair: Methods, Costs, and When to Act](https://foundationrepairlab.com/foundation-repair/)
- [Foundation Repair Companies: How to Compare Them](https://foundationrepairlab.com/foundation-repair-companies/)
- [Foundation Repair Company: What One Firm Should Do](https://foundationrepairlab.com/foundation-repair-company/)
- [Foundation Repair Contractor: Hiring the Right Crew](https://foundationrepairlab.com/foundation-repair-contractor/)
- [Foundation Repair Contractors: Licence, Bid, Contract](https://foundationrepairlab.com/foundation-repair-contractors/)
- [Foundation Repair Inspection: What It Covers](https://foundationrepairlab.com/foundation-repair-inspection/)
- [Foundation Repair Services: What Each One Covers](https://foundationrepairlab.com/foundation-repair-services/)
- [Foundation Repair Underpinning: Methods and Costs](https://foundationrepairlab.com/foundation-repair-underpinning/)
- [How a French Drain Works: Slope, Gravel, Pipe](https://foundationrepairlab.com/french-drain-how-it-works/)
- [Helical Piers for Foundation Repair: How They Work](https://foundationrepairlab.com/helical-piers-foundation-repair/)
- [How Helical Piers Work: Torque and Capacity](https://foundationrepairlab.com/helical-piers-how-it-works/)
- [Helical Tiebacks For Retaining Guide](https://foundationrepairlab.com/helical-tiebacks/)
- [Home Foundation Repair: The Owner's Decision Path](https://foundationrepairlab.com/home-foundation-repair/)
- [House Foundation Repair: A Diagnostic Order](https://foundationrepairlab.com/house-foundation-repair/)
- [How Push Piers Work for Foundation Repair](https://foundationrepairlab.com/how-do-push-piers-work/)
- [How Mudjacking Works: Slurry Lifting Explained](https://foundationrepairlab.com/how-does-mudjacking-work/)
- [How Long Does It Take to Repair a Foundation?](https://foundationrepairlab.com/how-long-does-it-take-to-repair-foundation/)
- [How to Pay for Foundation Repair: Six Options](https://foundationrepairlab.com/how-to-pay-for-foundation-repair/)
- [Is Foundation Repair Expensive? Compare Alternatives](https://foundationrepairlab.com/is-foundation-repair-expensive/)
- [JES Foundation Repair: Evaluating a Quote](https://foundationrepairlab.com/jes-foundation-repair/)
- [Olshan foundation repair](https://foundationrepairlab.com/olshan-foundation-repair/)
- [How Pier and Beam Leveling Works: A Step-by-Step Guide](https://foundationrepairlab.com/pier-and-beam-leveling/)
- [Pier foundation repair](https://foundationrepairlab.com/pier-foundation-repair/)
- [Polyurethane Foam Lifting Explained: Costs and Process](https://foundationrepairlab.com/polyurethane-foam-lifting/)
- [How Polyurethane Foam Lifting Works](https://foundationrepairlab.com/polyurethane-foam-lifting-how-it-works/)
- [Push pier foundation repair](https://foundationrepairlab.com/push-pier-foundation-repair/)
- [How Push Piers Work: Load Transfer Explained](https://foundationrepairlab.com/push-piers-how-it-works/)
- [Push Piers vs Helical Piers: How to Choose](https://foundationrepairlab.com/push-piers-vs-helical-piers/)
- [Re-Shimming a Pier and Beam Floor: Process and Cost](https://foundationrepairlab.com/re-shimming-pier-and-beam/)
- [How a Root Barrier Works: Panel, Depth, Roots](https://foundationrepairlab.com/root-barrier-how-it-works/)
- [Root Barriers: Do They Protect a Foundation?](https://foundationrepairlab.com/root-barrier-installation/)
- [Should I Buy a House With Foundation Repair?](https://foundationrepairlab.com/should-i-buy-a-house-with-foundation-repair/)
- [How Slab Lifting Works: Slurry, Foam, and Holes](https://foundationrepairlab.com/slab-lifting-how-it-works/)
- [Slab Lifting Methods Guide](https://foundationrepairlab.com/slab-lifting-methods/)
- [How Soil Stabilisation Works: Grout and Lime](https://foundationrepairlab.com/soil-stabilisation-how-it-works/)
- [Soil Stabilisation for Foundations: Methods and Costs](https://foundationrepairlab.com/soil-stabilization/)
- [Structural Foundation Repair: When It Is Required](https://foundationrepairlab.com/structural-foundation-repair/)
- [How a Sump Pump Works: Float, Pit, Check Valve](https://foundationrepairlab.com/sump-pump-how-it-works/)
- [Thrasher Foundation Repair: How to Read the Quote](https://foundationrepairlab.com/thrasher-foundation-repair/)
- [How Underpinning Works](https://foundationrepairlab.com/underpinning-how-it-works/)
- [Underpinning Methods: Pit, Pile, Beam and Soil](https://foundationrepairlab.com/underpinning-methods/)
- [Filling Voids Under a Slab: Methods and Costs](https://foundationrepairlab.com/void-filling-under-slab/)
- [Wall Anchors Explained: What They Do and Cost](https://foundationrepairlab.com/wall-anchors-explained/)
- [How Wall Anchors Work: Pulling a Wall Back](https://foundationrepairlab.com/wall-anchors-how-it-works/)