Pier Installation Guide: Push Piers vs. Helical Piers

Piers are the most reliable method for permanently stabilizing a settling foundation. They transfer the weight of your home from unstable surface soils down to bedrock or a competent load-bearing stratum. Once installed, piers stop settlement and can often lift the foundation back toward its original position. This guide covers the three main pier types, how installation works, what it costs, and how to choose the right contractor.

Types of Foundation Piers

Push Piers (Resistance Piers)

Push piers are galvanized or epoxy-coated steel tubes driven into the ground using the weight of the structure as resistance. A hydraulic ram pushes pier sections one at a time through a bracket attached to the foundation footing until the pier reaches bedrock or soil with enough bearing capacity to support the load.

Best for: Existing structures with enough weight to drive the piers. Homes with accessible bedrock or a competent stratum within 20-40 feet. Moderate to severe settlement.

Cost: $1,000-$3,000 per pier installed. A typical home needs 8-12 piers, putting most projects in the $10,000-$25,000 range.

Capacity: Each push pier typically supports 30,000-80,000 pounds depending on diameter and soil conditions.

Helical Piers (Screw Piles)

Helical piers are steel shafts with one or more helical (screw-shaped) plates welded to them. They are mechanically screwed into the ground using a hydraulic torque motor. The helical plates pull the pier into the soil like a wood screw into lumber. Installation torque is measured continuously and correlated to bearing capacity.

Best for: Lighter structures, new construction, areas with no bedrock within practical depth, expansive clay soils, and situations where the structure is too light to drive push piers. Also used for decks, porches, additions, and retaining walls.

Cost: $1,500-$3,500 per pier installed. A typical home needs 8-12 piers, putting most projects in the $12,000-$35,000 range.

Capacity: Each helical pier typically supports 20,000-$70,000 pounds depending on helix configuration and soil.

Slab Piers (Interior Piers)

Slab piers are push piers or helical piers installed through the interior of the slab. The slab is cored (a hole is cut through the concrete floor), the pier is driven through the opening, a bracket is attached, and the slab section is lifted. The core is patched with concrete.

Best for: Interior slab settlement where the perimeter walls are stable but the center of the slab has dropped. Common in slab-on-grade homes where plumbing leaks have eroded soil beneath the interior of the slab.

Cost: $1,500-$3,500 per pier. Interior piers cost more due to the need to cut and patch the slab and work in confined interior spaces.

How Push Pier Installation Works

Step 1: Excavation

The crew excavates soil along the foundation footing at each pier location. Holes are typically 3-4 feet wide and dug to the bottom of the footing. For exterior piers, this means removing landscaping, concrete, or other obstructions near the foundation wall.

Step 2: Bracket Attachment

A heavy steel bracket is placed beneath and against the footing. This bracket is the connection point between the pier and the foundation. It distributes the lifting force across the footing to prevent localized damage.

Step 3: Pier Driving

Steel pier sections (typically 2-3 feet long) are driven one at a time through the bracket into the ground using a hydraulic ram. The structure’s own weight provides the resistance. Each section is pinned or threaded to the next. Driving continues until the pier reaches refusal — the point where the soil or bedrock resistance exceeds the capacity needed to support the structure.

Step 4: Load Transfer and Lifting

Once all piers are driven, hydraulic jacks are placed on each pier simultaneously. The jacks apply upward force, transferring the building’s load from the failed soil to the pier system. If the goal includes lifting, the structure is raised incrementally (often over several hours) while the crew monitors for levelness.

Step 5: Locking and Backfill

The brackets are permanently locked to the piers with steel shims and hardware. The hydraulic jacks are removed. The excavated soil is backfilled and compacted. Concrete or landscaping is restored.

How Helical Pier Installation Works

The process is similar to push piers with key differences:

• No excavation is needed in many cases. Helical piers can be installed with smaller equipment and less soil disturbance, though some excavation at the footing is still required for retrofit applications.
• The pier is screwed in, not driven. A hydraulic torque motor rotates the pier into the ground. The operator monitors torque readings continuously. When the target torque is reached, the pier has achieved adequate bearing capacity.
• No structure weight is needed. This makes helical piers suitable for new construction where the building has not been placed yet, or for light structures like porches and decks.

The bracket attachment, load transfer, and locking steps are essentially the same as push piers.

Installation Timeline

Single day projects (1-4 piers): Small jobs involving 1-4 piers on accessible exteriors can be completed in a single day.

Two to three day projects (6-12 piers): The most common residential timeline. Day one is excavation and pier driving. Day two is lifting and locking. Day three (if needed) is backfill, concrete patching, and site cleanup.

Large or complex projects (12+ piers, interior work): May take 3-5 days. Interior slab piers add time for concrete cutting, working in confined spaces, and patching.

What to Expect During Installation

Noise. Hydraulic equipment generates moderate noise, similar to a skid steer or small excavator. Push pier driving creates rhythmic banging. Helical pier installation is quieter, producing a steady mechanical hum.

Vibration. Minimal. You may feel slight vibrations inside the home during push pier driving but nothing that would damage finishes.

Interior access. For slab piers, the crew will need access to specific interior areas. Furniture and flooring in those areas must be moved. The contractor should specify exactly which rooms are affected before work begins.

Landscaping disruption. Exterior piers require digging along the foundation. Expect disrupted flower beds, removed bushes, and displaced sidewalk or patio sections. A good contractor will restore these to reasonable condition, but plan for some touch-up landscaping afterward.

Utilities. The contractor will call 811 (or local equivalent) to mark underground utilities before digging. If gas, water, or electrical lines run close to the foundation, pier locations may need to be adjusted.

What to Expect After Installation

Most pier systems include a post-installation monitoring period. The contractor may return at 30 and 90 days to check pier performance and make minor adjustments.

Cracks in drywall, brick, or mortar may close partially or fully as the foundation levels. Wait 4-8 weeks after pier installation before repairing cosmetic damage — the structure needs time to settle into its new position.

Doors and windows that were sticking should begin operating more smoothly. Floors should feel more level. In some cases, especially with older homes or severe settlement, achieving perfect level is not realistic or even advisable — over-lifting can cause new damage.

Choosing a Contractor

Look for these qualifications:

• Manufacturer certification from the pier system they install (e.g., Foundation Supportworks, Ram Jack, Grip-Tite)
• At least 5 years in business with verifiable local references
• A structural engineer on staff or a working relationship with an independent engineer
• Written warranty of 25 years minimum, transferable to future owners
• Proper licensing and insurance (general liability and workers’ compensation)

Red flags:

• No written warranty or a warranty that is not transferable
• Pressure to sign immediately or steep discounts for same-day contracts
• A recommendation for significantly fewer piers than other bidders
• No engineer involvement on a complex project
• Unwillingness to provide references or proof of insurance

Get three quotes. Pier counts and spacing can vary between contractors. If one contractor recommends 6 piers and another recommends 12, ask each to explain their engineering rationale. More piers is not automatically better, but fewer piers spaced too far apart can leave unsupported spans that continue to settle.

Frequently Asked Questions

How long do foundation piers last? Galvanized steel piers installed to bedrock are considered permanent repairs. Manufacturers offer 25-year to lifetime warranties. The steel itself has a service life exceeding 75 years in most soil conditions when properly coated.

Can piers lift my foundation back to level? In many cases, yes. Push piers and helical piers can lift a foundation 1-4 inches or more. However, the goal is not always perfect level. The structural engineer or contractor will determine how much lift is safe based on the age of the home, the amount of settlement, and the risk of damage from lifting.

Do I need piers or would mudjacking work? Piers address foundation settlement by transferring loads to competent soil. Mudjacking and foam injection address slab settlement by filling voids. If your foundation footing has settled, you need piers. If only the slab surface has settled while the footings are stable, mudjacking or foam may be sufficient.

Will pier installation damage my plumbing? Pier locations are planned to avoid plumbing lines. In slab-on-grade homes, the contractor should camera-inspect sewer lines before and after work. Lifting a settled slab can occasionally stress or separate old cast iron drain pipes, so plumbing inspection is important.

How much does a structural engineer cost? A residential structural engineering inspection typically costs $300-$600. An engineered repair plan with drawings costs $500-$1,500. This is money well spent — it ensures the repair is designed correctly and gives you an independent opinion separate from the contractor’s sales process.

Can I stay in my home during pier installation? Yes. Most pier installations do not require you to vacate your home. There will be noise, some vibration, and construction activity around the perimeter, but the home remains safe and habitable throughout the process.