BENEFITS OF USING HELICAL PIERS
Whether you are the homeowner or the contractor, time is money. Helical piers reduce downtime for you on the job site. There is no waiting for inspector, concrete dry time, etc. It also causes minimal disruption to the yard/job site. The amount of footings that you must dig related to your jobs can cause a huge time/productivity loss to you as a contractor. Especially when you hate digging footing holes and mixing up concrete. When building with helical piers, it allows you to stop wearing out shovels and post hole diggers. There is no need to worry about the inspector arriving on schedule to look at footing holes — or about watching them fill up with water if he doesn’t show. Also, once a pier is installed, you know exactly how much weight it can support.
Steel Foundation
A helical pier is a manufactured steel foundation pin that is driven into the soil to a depth below the frostline using hydraulic machinery. Helical piers have been primarily used in heavy commercial work, but they are expanding and also well-suited for backyard decks, additions, sheds, etc.
Typical piers have a 7-foot shaft with a helical bearing plate welded to the end and a cap on top that attaches to the framing. All piers are load tested as installed so you as a contractor know exactly what weight it will support.
The load-bearing capacity of a helical pier usually relates to the amount of torque required to install it, a function of both the size of the helix and the soil’s bearing capacity. A pressure gauge on the installation machine reads the torque as the pier is rotated into the ground.
In weaker soil, the pier will be driven deeper to reach stronger soil. When the helix is below frostline and the pressure gauge hits a high enough number relative to the loading requirements of the structure, the installation is complete. To calculate the actual bearing capacity of the pier, the pressure reading is plugged into a formula called a torque correlation.
When poor soil conditions mandate going deeper than the standard-length shaft, an extension is added. Sometimes all it takes is a foot more depth to go from terrible soil to firm material. This is particularly relevant if building a freestanding deck where the piers close to the house might start out in backfill. If we were excavating to install a conventional concrete footing, we would have to dig down to virgin ground at the house foundation level — as much as 7 feet or 8 feet if the house had a basement. It is far easier to drive a helical pier to this depth.
Normally, we just power through loose rock, basketball-size and smaller. The installation machine generates sufficient torque for the helix to push rocks out of the way as it turns. Sometimes, the installer can steer the helix around a rock, then use the machine’s boom to pull the pier back into plumb. If we hit a large rock below frostline, the pile is parked on top of the rock and load tested. If it passes the load test, we can be confident the pier will never move. If it doesn’t pass the load test, the pier will be installed in a different spot.
In average soil, driving a helical pier takes about 10-20 minutes, after which it is ready to build on. Readings from installation are given to the inspector to show load rating. The pier and soil are verified during the installation to carry the load, so no settling or movement will happen in the future. Helical piers will give you the peace of mind that you won’t have to return to a job site due to footings heaving or moving later.
Steel Foundation
A helical pier is a manufactured steel foundation pin that is driven into the soil to a depth below the frostline using hydraulic machinery. Helical piers have been primarily used in heavy commercial work, but they are expanding and also well-suited for backyard decks, additions, sheds, etc.
Typical piers have a 7-foot shaft with a helical bearing plate welded to the end and a cap on top that attaches to the framing. All piers are load tested as installed so you as a contractor know exactly what weight it will support.
The load-bearing capacity of a helical pier usually relates to the amount of torque required to install it, a function of both the size of the helix and the soil’s bearing capacity. A pressure gauge on the installation machine reads the torque as the pier is rotated into the ground.
In weaker soil, the pier will be driven deeper to reach stronger soil. When the helix is below frostline and the pressure gauge hits a high enough number relative to the loading requirements of the structure, the installation is complete. To calculate the actual bearing capacity of the pier, the pressure reading is plugged into a formula called a torque correlation.
When poor soil conditions mandate going deeper than the standard-length shaft, an extension is added. Sometimes all it takes is a foot more depth to go from terrible soil to firm material. This is particularly relevant if building a freestanding deck where the piers close to the house might start out in backfill. If we were excavating to install a conventional concrete footing, we would have to dig down to virgin ground at the house foundation level — as much as 7 feet or 8 feet if the house had a basement. It is far easier to drive a helical pier to this depth.
Normally, we just power through loose rock, basketball-size and smaller. The installation machine generates sufficient torque for the helix to push rocks out of the way as it turns. Sometimes, the installer can steer the helix around a rock, then use the machine’s boom to pull the pier back into plumb. If we hit a large rock below frostline, the pile is parked on top of the rock and load tested. If it passes the load test, we can be confident the pier will never move. If it doesn’t pass the load test, the pier will be installed in a different spot.
In average soil, driving a helical pier takes about 10-20 minutes, after which it is ready to build on. Readings from installation are given to the inspector to show load rating. The pier and soil are verified during the installation to carry the load, so no settling or movement will happen in the future. Helical piers will give you the peace of mind that you won’t have to return to a job site due to footings heaving or moving later.