Quick answer
Push piers, also called resistance piers, are steel pipe sections pressed hydraulically through a bracket under an existing footing until they reach firm soil or rock, so the foundation rests on that deeper layer instead of the soil that moved.
The weight of the building supplies the force that drives them. Piers can stop further downward movement and, on some jobs, lift the structure. Which method and how many piers a house needs is an engineering decision.
Quick facts
The key facts about Push Piers, with sources:
- Type of deep foundation
- Displacement pier pushed in by hydraulic force 2
- Driving force comes from
- The weight of the structure acting as the reaction 1
- Works on
- Existing buildings, slabs, retaining structures and columns 1
- Can also do
- Lift the structure after the piers reach bearing 1
- Who designs the repair
- In North Carolina, a licensed engineer; other states differ 4
- Price
- Not quoted here; see the cost drivers section
Key takeaways
- A push pier is a steel tube pushed down beside or under a footing until it stops on dense soil or rock, then used to hold the footing up.
- The building pushes against itself: its own weight is the reaction force for the hydraulic ram 1.
- The pier carries load mainly at its tip, so it only works where a firm layer lies within reach 2.
- Piers stabilize a foundation. Lifting is a separate step that some jobs add and others skip 3.
- They do not fix the cause of movement, and no pier job can promise that movement will never return.
What push piers are and what they replace
General information, not a diagnosis of your house. A push pier is one of several ways to add deeper support under a foundation that is moving down.
The pier is a manufactured steel assembly: a head or bracket fixed to the foundation, mounted on steel pipe that runs down to bedrock or a firm layer of soil 1.
Makers call the same idea by other names. Resistance pier is the common one. All describe a pipe pushed into the ground by a hydraulic ram that reacts against the weight of the building 2.
The pier does not repair a crack or close a gap. It replaces the support that the upper, moving soil used to give. Engineers call that adding remedial supporting elements under an existing foundation 3. The broader field is covered in foundation underpinning.
Two cutaways of a footing. Left: a steel push pier pushed down through a bracket under the footing to firm soil. Right: a helical pier with spiral plates screwed down through a bracket under the footing. Both go below weak upper soil.
Illustrative drawing, not to scale and not a design. It shows two pier types carrying a footing down past weak soil to a firmer layer. Depths, spacing and loads are set by an engineer for each building.
Stabilizing is not lifting
Foundation stabilization means underpinning the foundation to limit future downward movement, whether or not the building is raised. Elevation adjustment means raising or lowering it to a new position 3. A push pier job can aim at either goal or both. Ask which one your plan is for.
How a push pier is driven, step by step
Manufacturers describe a two-stage process. The sequence below follows their technical material, not any one company’s crew.
- Access is opened. Brackets can be attached to the bottom or the side of an existing foundation, from the outside or from inside the building 1.
- A bracket is fixed to the footing. The bracket is the connection that will pass the building load into the pier 1.
- Pipe sections are pushed down. A hydraulic ram presses each section into the soil. The structure’s weight is the reaction, so the pipe advances against the building 2.
- The starter section reduces drag. A slightly oversized collar on the tip leaves a small gap around the shaft, which cuts side friction while driving. Depth is then set by resistance at the tip 2.
- Each pier is proof loaded. The manufacturer’s method drives the pier to a firm layer and tests it to a force greater than needed to lift the structure, which gives a measured margin of safety 1.
- The structure is lifted, if the plan calls for it. A manifold system can raise several piers together 1.
- The load is transferred and the pit is backfilled. The pier then holds the footing at its new support level.
No method fits every house
Pier type, count, depth and layout depend on building loads, soil layers, the footing’s strength and site access. They are not a rule of thumb. The manufacturer’s own manual says the design process should involve professional engineering input 1.
Push pier variations: where the bracket sits and how the pier starts
| Variation | What changes | Why it matters |
|---|---|---|
| Bracket under the footing or slab | The head attaches to the bottom of the foundation 1 | Used where the bracket can reach the underside of the concrete |
| Bracket on the side of the footing | The head attaches to the side of the foundation 1 | Lets the pier run beside the wall instead of under it |
| Bracket on a column | The head attaches to the sides of a circular or flat column 1 | Supports a single point load, such as a post |
| Exterior or interior driving | Piers can be installed outside or inside the building 1 | Interior work means breaking and patching the floor |
| Pre-drilled start | Pre-drilling can clear fill, boulders or similar barriers before pushing 1 | A way past obstructions that would otherwise stop the pier |
Example: how soil layers change the fit
The soil-layer example below is built from a manufacturer’s feasibility notes, not a recommendation for any site. Each row pairs a ground profile with what the manual says about push piers 1.
| Ground profile | What the manual notes | What it means in practice |
|---|---|---|
| Very soft or loose soil over a very dense layer | Described as an ideal situation for resistance piers | The pier can pass the weak soil and bear on the dense layer |
| Dense granular or stiff clay at modest depth | End-bearing support is expected once the tip reaches dense enough soil | A shallower depth to refusal is possible |
| Weak or potentially liquefiable zones | Column stability of the pier shaft must be considered | An engineer checks whether the thin shaft can stay straight under load |
| Rubble fill, boulders or voids | Such barriers may require pre-drilling | Borings or probes before the job find them early |
The same manual says a geotechnical investigation is used to locate the bearing layer, find weak zones, find barriers and make a first check of corrosion potential 1. See geotechnical soil investigation.
Where push piers are used, and where other tools fit better
The manufacturer says push piers are used mostly to underpin and repair homes and commercial buildings, retaining structures and slabs, and also on equipment foundations and towers 1. For homes, the usual setting is a footing that has settled because the upper soil is soft, wet, filled or shrinking.
They suit sites where a firm layer lies within reach of a ram pressing against the building.
They are less suited where that layer is out of reach, or where very dense soil sits close to the surface and stops the pipe early.
In those cases an engineer may look at helical piers or another deep system instead. The side-by-side view is on the push piers vs. helical piers page.
Foundation type matters too. A slab, a crawl space footing and a basement wall each give the bracket a different place to attach. The foundation types guide shows how each is built.
What push piers do well, and where they fall short
Strengths reported in technical sources
- Soil is displaced, not dug out, so there are no spoils to haul away 2.
- Installation can happen from inside a building where large machines cannot reach 1.
- Each pier is load tested as it goes in, which gives a measured result per pier 1.
- The same piers can lift the structure after reaching bearing 1.
- Support comes from a deeper layer than the soil that moved.
Limits to weigh
- A dense or hard layer must be reachable. Capacity depends mainly on the tip 2.
- Any extra side resistance is site specific and, per the maker, is only confirmable by load testing, which it calls typically not practical 2.
- The driving force is limited by the structure above, because the structure is the reaction 1.
- Soft zones can raise questions about shaft stability 1.
- A pier does not remove the cause of movement, such as water, trees or poor fill 4.
What push piers cannot promise
A push pier supports the footing it is attached to. It does not control moisture in the soil, and it does not repair a broken footing or a cracked wall.
North Carolina’s engineering board says there may be reasons for a failure that should be addressed, which is why the analysis comes before the repair 4.
Piers also do not guarantee that no future movement will occur. Soil nearby can still shrink, swell, wash out or settle.
Slabs and walls between piers can still crack if they are asked to span too far.
The manufacturer’s own design sheet notes that the wall and footing must be structurally able to span the gap between piers 1.
Capacity beyond the pier tip is another limit. The maker explains that displaced soil may add some side resistance over time, but how much depends on the site and can be confirmed only by load testing.
It says any added capacity may also be limited by how much strain the bearing material at the tip can take 2.
What drives the price of a push pier job
We do not quote prices. A fair number needs dated, local quotes, and the same house can be priced very differently depending on the scope.
The drivers, from the technical sources and from how the work is done, are the number of piers, how deep each must go to reach bearing, and whether the plan stabilizes only or also lifts.
Access matters. Interior piers mean removing concrete for access holes and patching it afterward 3, and tight spaces slow the crew. Obstructions that need pre-drilling add time 1. Engineering and design, permits, utility locates and finishing work all add line items, as does any drainage fix that treats the cause.
Use the repair cost guide to see how quotes are built, the cost calculator for a planning range, and the pier count estimator to understand why counts vary. The estimator is a teaching aid. It does not replace an engineer’s layout.
From first concern to finished pier job
- Get an evaluation first. North Carolina’s board states that a statement that a foundation has failed, or that structural repair is needed, should be made by a licensed engineer who evaluated the conditions 4. Our engineer guide explains when to call one.
- Check the soil. Borings or probes find the bearing layer and any barriers 1.
- Get a written plan. The plan should show pier locations, the goal (stabilize or lift) and who is responsible.
- Compare scope, not price alone. Use the contractor guide and the repair method tool to prepare questions.
- Watch the installation. Each pier is driven and tested; the log should be kept.
- Track the result. Record elevations before and after. The elevation log helps.
Keeping the foundation steady after the piers are in
Piers hold the footing. The rest of the site still needs care.
- Keep gutters clear and downspouts discharging away from the wall. See drainage and grading.
- Check that soil near the wall still slopes away. Adding a few inches of soil to a low spot is a safe homeowner task.
- Photograph and date any new crack, and note which doors or windows stick.
- Keep the installer’s pier map, test records and warranty. See warranties.
- Ask your engineer whether to monitor elevations, and for how long.
Risks, unknowns and when to call an engineer
- Unknown ground. Fill, voids and boulders can stop or bend a pier, which is why probes come first 1.
- Corrosion. Steel in soil can corrode, so a first look at corrosion potential belongs in the soil investigation 1.
- Spacing. If piers are too far apart for the wall or footing to span, cracks can continue between them 1.
- Uneven lifting. Lifting raises the whole structure and can stress finishes and pipes; an engineer sets the plan.
- Underground lines. Utilities and plumbing under the slab need to be located and checked.
Call a licensed structural engineer when
Movement is large, widening or changing; walls are bowing or displaced; doors and windows stick together with new cracks; a corner is separating; or anything about the building feels unsafe. Do not dig beside a foundation, jack a house or enter a crawl space with standing water yourself.
Codes, evaluation reports and who may design the repair
Deep foundation elements fall under the deep foundation provisions of the International Building Code, and the manufacturer says two models complied with the structural provisions of the 2000 International Building Code, according to an older evaluation report 1.
Ask for the current evaluation status, and check the code edition and amendments your jurisdiction adopted, since they vary.
The rules for who may design the repair also vary by state.
North Carolina’s Board of Examiners for Engineers and Surveyors says a licensed engineer must make the preliminary analysis and judgment on methods of repair, including the number and location of support piers, and that a repair company cannot leave design to the product maker 4. Other states differ. Check your state board.
A credential is not a license, and a manufacturer’s training is not a license. Confirm each license with the issuing board. The vetting page explains how we think about credentials.
Push piers next to other lifting and support methods
| Method | How it goes in | Main load path | Common limit |
|---|---|---|---|
| Push piers | Steel pipe pressed in by hydraulic ram 2 | End bearing at the tip 2 | Needs a firm layer within reach |
| Helical piers | Steel shaft with plates, screwed in with torque 5 | Bearing on the helix plates 5 | Hard rock or shallow bedrock 5 |
| Pressed concrete piers | Short concrete segments pressed in one by one 3 | Mostly skin friction, some end bearing 3 | Dense granular soil resists driving 3 |
| Drilled piers | Hole drilled and filled with concrete 6 | End bearing and side resistance 6 | Caving or wet soil needs casing or slurry 6 |
| Mudjacking | Grout pumped under a slab 7 | Fills voids; does not add deep support 7 | Not a deep foundation fix |
Push pier myths worth correcting
- Myth Push piers always lift the house back to level.
- Reality Lifting is an optional second stage and depends on the plan; stabilizing and lifting are separate goals 3.
- Myth Every pier goes to bedrock.
- Reality Piers go to a firm bearing layer. That may be dense soil rather than rock 1.
- Myth More piers always means a better repair.
- Reality Count and spacing come from loads and the foundation’s ability to span. Bigger counts are not a quality measure by themselves 1.
- Myth A pier job fixes the cause of the problem.
- Reality Water, trees and fill can still act on the soil near the foundation 4.
- Myth Piers make future movement impossible.
- Reality No source we read says that, and none can: the soil outside the piers can still move.
Regional soil: why piers are common in some areas
Expansive clay is prevalent in Texas and along the Gulf Coast, the Appalachian states, the Southwest and the Great Plains, according to the Federal Highway Administration’s drilled shaft manual, which counts about twenty states where expansive clays are a problem to some degree 6.
In those regions, deeper support is a common repair topic. In regions with frost, the frost depth and frost-susceptible soils change how a footing behaves. The right answer in one region is not automatically right in another.
Is a push pier plan worth discussing with your engineer?
A push pier plan is worth discussing when a footing has moved down, a firm layer lies within reach, and the cause of the movement can be addressed or is understood. It is less clear where the movement is cyclical or upward, or where the firm layer is out of reach.
The decision guide below turns that into questions to take to a licensed engineer. It is not a prescription for any house. For the broader menu, see repair methods and foundation repair.
- If The footing moved down and the cause is known
- Then Ask the engineer whether deep support suits the soil and loads
- If The ground may be moving up or cycling with moisture
- Then Ask whether a pier that does not resist uplift is the right tool; see settlement vs. heave
- If A firm layer is unconfirmed
- Then Ask for borings or probes before any pier count is set
- If The plan only mentions price and pier count
- Then Ask for the design basis, who stamped it and the test records
Engineer first, contractor second
A structural engineer evaluates the cause and sets the method. A contractor installs it. Where the engineer and the contractor are the same company, ask who is accountable for the design.
Questions about Push Piers
What is a push pier?
A push pier is a steel pipe pressed down through a bracket on a footing until it reaches firm soil or rock, so the footing is supported from below. The building’s own weight is the reaction force for the hydraulic ram, according to the manufacturer’s technical manual. It is also called a resistance pier.
How do push piers work?
A bracket is fixed to the foundation, and pipe sections are pushed through it into the ground.
When the tip stops on a dense or hard layer, the pier mostly carries load at the tip. The system can then lift the structure if the plan calls for it. Some makers load test each pier as it goes in.
Do push piers lift a house?
They can, but not every job does. Lifting is a second stage after the piers are driven to a firm layer. Engineers separate stabilizing, which limits future downward movement, from elevation adjustment, which raises or lowers the structure. Your plan should say which one it is for.
How deep do push piers go?
Depth varies by site. Each pier is pressed until the tip meets enough resistance in a dense or hard layer, so depths differ from pier to pier on the same house. A geotechnical investigation helps locate that layer before work starts. We do not give a typical depth, because it would mislead.
Are push piers permanent?
A steel pier is designed as a lasting support, but no source supports a promise that a foundation will never move again. Soil around the piers can still change with water, trees and fill. Corrosion potential is part of the soil investigation. Ask for the warranty terms in writing.
What soils do push piers work in?
They need a layer firm enough to stop the tip, with the weak soil above it. A manufacturer calls very soft soil over very dense soil an ideal case. Fill, boulders or voids can require pre-drilling. A boring or probe is how you learn which case you have.
Do I need an engineer before installing push piers?
In North Carolina, the engineering board says a licensed engineer must make the analysis and design of repair, including pier number and location. Other states differ, so check your state board. Even where it is not required, an independent engineer can compare plans.
Can push piers fix a bowing basement wall?
Piers support footings, not walls. A bowing wall is moved by soil and water pressure, which piers do not address. Wall repairs use different methods chosen by an engineer. Our bowing wall page explains the difference, and the repair methods guide shows how the options fit together.
How much do push piers cost?
We do not publish prices. The main drivers are the number of piers, their depth, access, whether the job lifts as well as stabilizes, engineering and permits. Our cost guide and calculator show how quotes are built so you can compare scopes line by line.
Sources
- Hubbell Power Systems (CHANCE), Technical Design Manual, Edition 3 (2014): resistance pier and helical sections. Manufacturer document, retrieved .
- Hubbell Power Systems, Foundation Solutions blog: Push Piers, Frictional or End Bearing? Manufacturer document, retrieved .
- Foundation Performance Association, FPA-SC-08-1: Design, Manufacture, and Installation Guidelines of Precast Concrete Segmented Piles for Foundation Underpinning (2014), definitions, retrieved .
- North Carolina Board of Examiners for Engineers and Surveyors, Foundation Repair Guidelines (revised 10/22/2024), retrieved .
- Iowa State University Bridge Engineering Center and InTrans, Helical Pile Foundation Guide for Bridge Structures (October 2023), retrieved .
- Federal Highway Administration, Drilled Shafts: Construction Procedures and LRFD Design Methods, GEC 10, FHWA-NHI-10-016 (May 2010), retrieved .
- Federal Highway Administration, Concrete Pavement Preservation Guide, 2nd ed., FHWA-HIF-14-014 (2014), Chapter 4: Slab Stabilization and Slab Jacking, retrieved .
Expert review
Written by the HyreFoundation Research team. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.
How the numbers were checked: How a push pier works, how it is installed, proof loading, feasibility notes and bracket variations come from one manufacturer’s technical manual and one manufacturer blog post, both labeled as manufacturer documents.
Definitions of stabilization and elevation adjustment come from a Foundation Performance Association committee guideline. Licensing statements come from the North Carolina engineering board. Comparison cells cite the sources for the other methods.
No prices, depths, spacing or loads are given. Rules checked 2026-10-14. General information, not engineering advice.
Suggest a correction. We fix errors and say what changed.