A screw pile foundation is only as good as its installation. The steel can be engineered perfectly, but if a pile goes in off-line, advances like an auger, or stops short of its target torque, the foundation won’t perform the way it was designed to.
This guide covers how screw piles are installed properly, what installation contractors should be monitoring on every pile, and how capacity is verified in the field. It’s written for foundation contractors, engineers and project managers working with helical piles in Alberta and Western Canada.
How a Screw Pile Is Installed
A screw pile (also called a helical pile) is a steel shaft with one or more helical bearing plates welded to it. It isn’t driven, hammered or poured. It’s rotated into the ground with a hydraulic torque head mounted on compact equipment, and the helix pulls the pile down through the soil like a screw.
That’s the method. There’s no pile driver, no excavation and no concrete. Everything else in this guide is about doing that one method well.
Step 1: Engineering and Site Review
Before a pile goes in the ground, the job needs:
- A geotechnical report describing soil layers, groundwater and frost depth
- Structural loads for each pile location (compression, tension and lateral, where they apply)
- A pile specification from the engineer: shaft size, helix configuration, minimum embedment depth and minimum installation torque
In Alberta, piles are typically taken below the frost line to protect against frost heave. Final depth is set by the engineer and confirmed in the field by installation torque.
Step 2: Locates and Site Layout
No ground disturbance should start without utility locates. In Alberta, locate requests go through Utility Safety Partners (formerly Alberta One-Call) using Click Before You Dig. They recommend requesting locates at least 3–5 days ahead, and longer during the busy May–September season. Mark the work area, confirm private and overhead lines, and make sure operators have the locate paperwork before starting.
Pile positions are then laid out to the foundation plan. Accuracy here matters, because every downstream trade builds off these locations.
Step 3: Set Up and Plumb the Pile
The pile is connected to the torque head and set at its marked position. It’s aligned to the angle the design calls for (usually plumb, sometimes battered for lateral or tension loads). Alignment should be checked as the first section goes in. Correcting a pile that starts off-line is far easier in the first few feet than at depth.
Step 4: Rotate, Don’t Auger
This is the step that separates good installations from poor ones.
The pile should advance roughly one helix pitch per full revolution. That’s what a true helix is designed to do: thread cleanly through the soil with minimal disturbance. To keep that rate, the operator applies steady downward pressure (crowd) while rotating at a controlled speed.
If the pile spins without advancing, it starts acting like an auger and churns the soil around the helix. That disturbed soil weakens the bearing layer. It also breaks the relationship between installation torque and capacity, which is the basis for verifying the pile.
This is where helix geometry matters. Inland’s True Pitch™ helices are pressed to a true pitch with a constant slope and a right angle to the shaft. A bevelled leading edge cuts cleanly through dense and frozen soils with less slippage. A consistent helix advances predictably, which makes the operator’s job, and the torque readings, more reliable.
Step 5: Monitor Torque Continuously
Installation torque is the single most important number on a screw pile job. As the helix advances, the resistance it meets is directly related to the soil’s bearing capacity. The engineer uses published torque correlation factors (commonly those in ICC-ES AC358) or site-specific load test results to convert torque into capacity.
Best practice:
- Use a torque indicator that measures torque directly, and keep the equipment calibrated
- Record torque against depth for every pile, not just at the end
- Watch for sudden changes. A sharp jump can mean an obstruction rather than a good bearing layer. A sudden drop can mean a soft layer or that the pile has started augering.
Step 6: Meet Both Termination Criteria
A pile is complete when it has reached both the engineer’s minimum embedment depth and the minimum installation torque. Hitting one without the other isn’t a finished pile:
- Torque reached too shallow: the pile may be sitting on an obstruction or a thin hard layer. Don’t stop. Report it to the engineer.
- Depth reached without torque: the pile needs to go deeper, or the engineer may revise the design (longer pile, larger helix or added helix).
If more length is needed, extension sections are added and the pile continues to advance.
Step 7: Cut, Cap and Document
Once a pile meets its criteria, it’s cut to the design elevation and fitted with the specified cap or bracket. Screw piles connect to a wide range of structures through caps, brackets and tiebacks.
Every pile gets an installation record: location, pile type, final depth, torque readings and the final installation torque. These logs give the structural engineer documented, pile-by-pile proof that the design requirements were met. Concrete foundations simply can’t offer that.
When Load Testing Is Used
Torque correlation is the standard method for verifying capacity on most projects. On larger commercial and industrial work, the engineer may also call for full-scale load tests on selected piles. These are typically done under ASTM D1143 (axial compression) and ASTM D3689 (axial tension). Load tests confirm the torque-to-capacity relationship for that specific site. They can justify higher design capacities and, in some cases, fewer piles.
Dealing with Difficult Ground
- Frozen ground: screw piles can be installed through winter conditions that stop concrete work entirely. A bevelled leading edge helps the helix cut through frozen and dense soil.
- Cobbles, debris or very dense layers: where the engineer allows it, a pilot hole may be pre-drilled to get past an obstruction. If a pile can’t reach its depth and torque criteria, the engineer decides the next step.
- Soft soils, backfill and high water tables: the pile bypasses weak surface material and bears in competent soil below. Torque monitoring confirms when that layer has been reached.
Corrosion Protection
Steel piles are designed for the soil they’re installed in. Corrosion is typically addressed through the design (for example, allowing for steel loss over the service life) and coatings such as hot-dip galvanizing where the engineer specifies them. Soil resistivity and chemistry from the geotechnical report should drive that decision.
Safety on Site
Screw pile installation is low-noise and low-vibration, but it still involves heavy hydraulic equipment and high torque. Every crew should have:
- Proper PPE: hard hats, safety boots, gloves, eye protection and high-visibility clothing
- A site-specific hazard assessment, including locates, overhead lines and equipment travel paths
- A clear exclusion zone around the rotating pile and torque head
- Trained operators and routine equipment inspections, including hydraulic lines and the drive head
Inland Screw Piling holds ISNetworld and COR/AASP certification, and our products are made under CWB-certified welding and G-CERT ISO 9001:2015 quality management.
Proven on Real Projects
Inland was contracted directly by Orbis Engineering to engineer, fabricate and install 709 screw piles for the Hut 8 facility in Medicine Hat, Alberta. The project supported 40 modular data centre units, transformers, a pipe rack and a communications tower, plus full cutting and capping. It finished two months ahead of schedule.
Work with Inland Screw Piling
Inland engineers and manufactures True Pitch™ helix screw piles in Coaldale, Alberta, and installs them across the province with our own crews. Outside Alberta, we supply piles and connect projects with a vetted installation partner. If you’re a contractor, we also offer a certified installer program for True Pitch™ piles.
Have a project coming up? Call us at 403-345-6781 or request a quote.
