Are you worried that push pier foundation repair will turn your property and your sanity upside-down? Are you concerned about the alien mechanics of it all – the ruckus of heavy machinery, strangers traipsing through your backyard, and the transplanting of your favorite petunia bush? Or maybe you’re apprehensive that the “foundation repair” will result in further structural or cosmetic damage. If so, this article is for you.
All the concerns listed above, and more, are completely normal. Dalinghaus Construction Inc. has over 100 years of collective experience in the foundation repair game. After servicing thousands of foundations in Southern California and Arizona, we understand push pier foundation repair can prove a daunting experience. Rest assured; we educate so you can emotionally regulate.
This article covers the definition of a push pier system and the push pier installation process (from pier excavations to the final project walkthrough). By the end of this article, you will understand the basic functionality of push pier systems and feel confident in their ability to secure your foundation against further foundation settlement.
What Does Push Pier Installation Look Like?
What are Push Piers?
So, let’s start with the barebone basics. What, exactly, is a push pier?
Push piers are galvanized-contractor-grade-steel pipes 3.5 feet in length that are hydraulically driven to competent, load-bearing soil and securely anchored to a foundation’s prepped footing (via a remedial bracket) to secure, stabilize, and/or lift a structure.
Now, at first glance, the definition above might appear a bit dense (it’s not Pidgeon English, we promise).
In essence, push pier systems are underground stilts that support your home above incompetent, non-load-bearing soil (the muck that caused all your signs and symptoms in the first place). The desired depth is reached by adding additional sections of pipe that have a slip-in coupling that fits the push piers together snugly – allowing you to chain pipe until you hit bedrock.
Push piers are an elegant solution for combating foundation settlement. First of all, push piers are galvanized to impede rust and oxidization – meaning these steel pipes can ward off water damage despite seasonal rains or other sources of moisture.
And, of course, push piers are remarkably strong, boasting a maximum load capacity of 68 thousand pounds. Every foundation repair project is different, so push piers come with some size variation (and consequent flexibility) to fit your particular need. Push piers are measured by the diameter of the pipe and range in size from 2-7/8”, 3.5”, and 4.5”.
Finally, push piers are generally driven to 25-30 feet. Dalinghaus Construction has gone as shallow as 10 feet and as deep as a whopping 150 feet. In short, push piers are a system of interlocking pipes that act as a rust-proof underground stilt system that can be driven to competent, load-bearing soil and provide decades of foundational support.
Push Pier Excavation & Fitting the Remedial Bracket
The single most important aspect of the excavation process is access. The affected area must be accessible, so any debris or impediments must be removed, such as sidewalks, cement patios, or flowerbeds. The concrete will be replaced upon the completion of the project (or as determined by the contract) and the shrubbery will be returned.
Push pier excavations are steps numero uno in the push pier installation process. Turns out, there’s a heckuva lot of digging in the foundation repair business. Now, don’t let the word “excavation” fool you, we’re not looking for dinosaurs – it’s just a 3×3 foot hole (usually 18-24 inches deep) that allows us access to the foundation footing.
These “excavation sites” are demarcated by stickers or painter’s tape (an easy-to-remove marker so as not to ruin the house siding/stucco) every 6 feet per the designed repair plan.
After the foundation footing has been reached, the concrete footing is demo-hammered down to a flat surface capable of housing the remedial bracket. The remedial bracket fits the footing in an L shape and allows the drive stand to attach later to guide/drive the push piers down to competent, load-bearing soil.
The remedial bracket is attached to the footing by “redhead” bolts with expanding ends that lock into the cement place after implementation. The remedial bracket is then securely attached to these bolts with a washer and nut. Tighten screws can also be utilized to attach the remedial bracket to the home’s footing.
Push Pier Installation
After the remedial bracket is installed, the drive stand is attached to begin driving push piers down to competent, load-bearing soil. The drive stand serves a twofold purpose – it acts as a push pier guide (the chamber to the bullet/pier, so to speak) and houses the hydraulic ram system.
This part of the push pier installation is generally carried out by a single production crew member (the other two team members digging excavations or attaching remedial bracket hardware). The single crew member has the estimated amount of required pipe within easy reach and begins to drive steel, loading it into the drive stand and utilizing the hydraulic ram to push the pier into the earth (hence the name, push piers).
The process is rinsed and repeated until the push piers have reached the required depth.
Push Pier Load Transfer (Lift or Stabilization)
After all the push piers have been installed, the home is ready to be lifted back to maximum practical recovery and/or stabilized. If you choose not to lift your home, meaning you simply want to stabilize the home from further settlement, the remedial brackets are capped.
Lifting your home does not pose a threat to the structural integrity of your home.
If you choose to lift back to maximum practical recovery, which most homeowners do, we utilize a hydraulic lift cylinder at each push pier location. These hydraulic cylinders are controlled by valves and lift the home in unison (during which time Ziplevel floors measurements are repeatedly taken to ensure a controlled, level lift). As certain areas of the home return to level, the corresponding hydraulic cylinders are turned off, allowing the other cylinders to continue to lift.
Read more: What Is A Pier Foundation?
We continue to lift, measure, and shut off lift cylinder valves until the home has been returned to a level position. Once the lift is completed, we tighten up the push pier hardware and remove the cylinders from the piers.
Lifting a home to maximum practical recovery can take 2-3 hours.
Phenomenon one can expect during a lift are:
- Cracked drywall closing back togetherSloped floors evening out
- Slanted window and doorframes returning to square
- Doors become easier to open/close
Void Fill /Post-and-pad Adjustments for Push Pier Repair
During the push pier foundation repair lift, voids are created underneath your foundation. Depending on the type of foundation you have (slab or raised), the interior floor will need to be supported due to the exterior/outer edge of the foundation’s new higher position.
For slab on grade foundations, polyurethane is utilized, injected between the bottom of the foundation’s slab and the soils to fill the newly created gaps and re-support the structure.
For raised foundations, posts and pads will need to be adjusted to fill the gaps to ensure there is contact with the girder beams that support the subfloor. Busted posts and pads are removed and replaced to ensure the floor is supported.
Push Pier Final Walkthrough
After the push pier lift and stabilization, the final walkthrough can take place – a cursory visual of the previously affected areas with careful attention paid to:
- Previous stucco cracks
- Previous drywall cracks
- Previously sloped floors
- Chimneys (chimneys often have their own, mini foundation)
In addition to visual cues, floor elevation measurements are taken again to compare to the floor elevations during the initial foundation inspection.
Push Pier Excavation Backfill
After the final repair walkthrough, the excavation holes are backfilled, the concrete is repoured, and/or the shrubs are replanted.
This is by far the easiest step in the foundation repair process.
Enjoy Your Dalinghaus Lifetime Warranty
In this article, you learned the definition of a steel push pier system and fully understand the installation process, from excavations to lift. You should now feel absolutely confident and secure in your choice to repair your foundation via push piers.
Dalinghaus Construction Inc. has over 100 years of combined foundation repair experience. We know that fear resides in mystery, which is why we broke the push pier system installation down to the bare essentials.
All that’s left to do is sit back, relax, and enjoy your push pier lifetime warranty. To learn more about the benefits of your lifetime warranty, like how it’s inheritable and transferable upon purchase, read our article Dalinghaus Steel System Lifetime Warranty: Push Piers, Helical Piers, & Helical Tiebacks.