Push Pier vs Helical Pier: Which Is Right for North Shore Foundations?

Published April 29, 2026 by North Shore Foundation Pros

If a contractor has told you that your Glenview, Wilmette, or Northbrook home needs underpinning, you've probably heard the words "push pier" and "helical pier" in the same conversation. Both are proven foundation repair methods. Both will stop settlement and, in many cases, lift a sunken slab back toward its original elevation. But they aren't interchangeable. The right choice depends on your home's weight, the soil under your foundation, and what part of the structure is failing.

This guide walks through how each system works, where each one wins, and what to ask the contractor who hands you the estimate. If you'd rather skip the homework and have someone look at your foundation in person, you can request a free inspection and we'll give you a written assessment.

How Push Piers Work

A push pier is a hollow steel tube, usually about 3 inches in diameter, driven straight down through the soil under your foundation footing. The crew excavates a small pit at each pier location, bolts a steel bracket to the underside of the footing, and uses a hydraulic ram braced against the bracket to push pier sections into the ground one at a time. Each new section gets coupled to the last as the column descends.

The pier keeps advancing until it hits "refusal," which means the soil is dense enough that the available pushing force can't drive the pier any deeper. On the North Shore, refusal often happens in glacial till or stiff lacustrine clay between 25 and 60 feet down. Once every pier reaches refusal, the contractor uses synchronized hydraulics to transfer the home's weight onto the piers. At that point your house is being supported by the piers, not by the failing soil that caused the settlement.

Push piers depend on weight to work. The heavier the home, the more force is available to drive each pier. That's why push piers are typically the right call for two-story brick or stone homes, large additions, and any structure with masonry chimneys or substantial roof loads.

How Helical Piers Work

A helical pier looks a bit like a giant steel screw. The shaft is square or round steel, and one or more helix-shaped plates are welded near the tip. A hydraulic torque motor turns the pier into the ground. As the helix bites into the soil, it pulls the pier deeper, much like a wood screw advancing into a board.

Installers monitor torque as the pier advances. Torque correlates predictably with soil bearing capacity, so when the pier hits a target torque value (set by the project engineer), the crew knows it has reached load-bearing soil. The pier is then connected to a bracket on the footing or wall, and the home's load is transferred onto the helical column.

Because helical piers don't need the building's weight to install, they generate their full design capacity from the moment they're seated. That makes them the standard for new construction support, additions, light commercial buildings, and detached structures like garages and three-season rooms. They're also the right choice for homes with light wood framing or shallow basements, where there isn't enough mass available to drive a push pier to refusal.

Side-by-Side Comparison

Why Soil on the North Shore Matters

The Chicago North Shore sits on a layered mix of glacial deposits laid down by the retreating Wisconsin glaciation about 14,000 years ago. The top several feet are typically stiff to firm clay, sometimes with sand seams. Below that you may hit silty clay, lacustrine clay (very fine, water-sensitive lake-bottom material), and eventually denser till. Bedrock is rarely a concern because it sits hundreds of feet below the surface in most North Shore towns.

This soil profile matters for pier selection in two ways. First, the upper clays expand when wet and shrink when dry. That's the engine behind a lot of foundation movement around Glenview, Wilmette, Winnetka, and Highland Park, especially after wet springs followed by dry summers. Second, the load-bearing layer that piers need to anchor into can be deep, so push piers may need to drive 40 feet or more before hitting refusal. Helical piers can sometimes find an adequate bearing layer shallower than that, depending on the lot.

A reputable contractor will pull soil borings or at minimum review the local geotechnical history before specifying piers. If anyone hands you a quote without asking what the dirt looks like, that's a red flag.

When Each Method Is the Right Choice

Push Piers Are Usually Right When

• The structure is a two-story home with masonry, brick, or stone exterior.
• You're underpinning the main load-bearing perimeter of an existing building.
• Soil reports show a deep, dense bearing stratum the pier can drive to.
• Cost per linear foot of foundation matters and the home is heavy enough to drive piers efficiently.
• You need a pier system with a long, well-documented track record on similar Chicago-area homes.

Helical Piers Are Usually Right When

• You're supporting an addition, deck, porch, sunroom, or detached garage.
• The structure is light-framed (single-story wood frame, ranch, raised slab).
• Soil borings show a competent bearing layer at moderate depth.
• You need verified load capacity at install (helical pier torque correlates directly to capacity).
• The job is new construction support, where push piers physically can't be used.
• Access is tight and smaller equipment is required.

Cost Expectations for North Shore Homeowners (2026)

Expect to spend somewhere between $18,000 and $45,000 for a typical North Shore foundation underpinning project, depending on the number of piers, the pier type, and how much restoration work is needed. Most homes need 6 to 14 piers on average.

Push piers run $1,800 to $2,800 each installed, including the bracket, excavation, and load transfer. Helical piers usually run $2,000 to $3,200 each. The helical premium pays for the torque-verified capacity and the smaller crew footprint. For a deeper breakdown of pricing, including foundation crack repair, basement waterproofing, and full underpinning, see our foundation repair cost guide.

Two cost factors that surprise homeowners: hardscape restoration (concrete patios, brick walks, retaining walls that have to be cut and replaced) and interior finish work (drywall, flooring, trim that may need touch-up after lift). Get those line items in writing on your estimate.

What to Ask Before You Sign a Contract

1. Are the piers manufactured to ICC-ES certification? Ask for the report number.
2. Is the installer certified by the pier manufacturer? Ask for proof.
3. Will the project be designed and stamped by an Illinois licensed structural or geotechnical engineer?
4. What is the written warranty? Lifetime, transferable, and signed by the company and the manufacturer is the gold standard.
5. How is load transfer verified? Push piers should show a hydraulic pressure log per pier. Helical piers should show a torque log per pier.
6. What's included in restoration? Get specifics on excavation backfill, sod, hardscape, and interior cosmetic repair.
7. Is foundation movement covered by my homeowners insurance? Most policies exclude settlement, but it's worth checking your declarations page.

If a contractor pushes back on these questions, walk away. Foundation repair is a permanent decision and the documentation should be permanent too. We've seen homeowners in Northbrook and Deerfield burned by bargain installers who skipped the engineer or used uncertified piers, and the cleanup is more expensive than doing it right the first time.

Frequently Asked Questions

Which is cheaper, push piers or helical piers?

Push piers are usually cheaper per pier on the North Shore, often by 10 to 20 percent, because installation is faster and uses less specialized equipment. Helical piers can match or beat push pier total cost when fewer piers are needed, which happens with lighter homes or when bedrock is shallow.

How deep do push piers and helical piers go in Glenview area soils?

On the North Shore, push piers commonly drive between 25 and 60 feet to reach refusal in firm clay or glacial till. Helical piers usually anchor between 15 and 35 feet, since they screw into a load-bearing layer rather than chasing bedrock. Final depth depends on soil logs at your specific lot.

Will push pier or helical pier installation damage my landscaping?

Both methods need a small excavation at each pier location, usually 3 by 4 feet wide and 4 feet deep. Helical pier installation is slightly less invasive since hydraulic equipment is smaller, but a competent crew restores grass, plantings and grade after either install. Hardscape under the pier line will need to be cut and patched.

Do helical piers work for new additions and porches?

Yes. Helical piers are the preferred choice for new construction support, additions, decks, and porches because they generate immediate load capacity without needing the building's weight to drive them. Push piers require existing structural weight to advance, so they only work for retrofitting an already-built home.

Which option has the better warranty?

Reputable installers in Illinois warranty both systems for the life of the structure, transferable to future owners. The warranty quality depends on the contractor and the manufacturer, not the pier type. Ask for the written warranty document, the manufacturer name, and proof the installer is certified by that manufacturer.

Can I have both push and helical piers on the same project?

Yes, and it's more common than people think. A heavy main house may take push piers along the load-bearing perimeter while a lighter porch, garage extension or bay window gets helical piers. A good engineer or installer will spec the right tool for each section instead of forcing one method everywhere.

Whichever method ends up being right for your home, the underpinning system is only as good as the people installing it. Get bids from at least two licensed, certified installers, ask for the engineering report, and read the warranty word for word. If you'd like a second opinion on a quote you've already received, we're happy to look it over.

Related reading: Bowing Basement Walls: Causes and Repair Options | Helical Piers Installation Service | Foundation Crack Repair