Method Guide
Push piers, helical piers and slab piers compared
All three do the same job, which is to take load off soil that is moving and put it on material that is not. They differ in how they get down there, how their capacity is verified, and what kind of structure they suit.
Push piers
A push pier is a plain steel tube, section by section, driven vertically into the ground by a hydraulic ram that reacts against the weight of the house itself. Because the house is the reaction mass, the pier cannot be driven harder than the structure above it can resist, which means every pier is effectively load tested during installation. Installation pressure is recorded for each one, and that record is the closest thing residential foundation work has to proof of capacity.
The catch is the same as the advantage. If the structure is too light, there is not enough reaction to drive the pier to bearing. Single-storey slab construction, porches, stoops, additions and light framing all fall into that category.
- Best for: heavier two-storey construction, full-masonry houses, perimeter footings on a house with enough dead load.
- Verification: hydraulic pressure logged per pier.
- Depth: whatever it takes, discovered during driving.
Helical piers
A helical pier is a steel shaft with one or more helix plates welded to it, screwed into the ground by a hydraulic drive head. It does not need the building for reaction, so it can be installed under light structures and can be installed before a structure exists at all, which is why it also appears in new construction on poor soil.
Capacity is verified by installation torque, which correlates with the resistance the helices are meeting. A torque reading is a less direct proof than a load test but it is a genuine measurement, taken continuously, and it is recorded per pier.
- Best for: light structures, additions, porches, stoops, garages, crawl space perimeters, and any situation where the building cannot provide reaction.
- Verification: installation torque logged per pier.
- Also used for: tiebacks and wall anchors, where the same shaft is installed horizontally into soil behind a bowing wall.
Slab piers
Sometimes the low point is not at the perimeter. On a slab-on-grade house, an interior bearing point carrying a load-bearing wall or a column can settle while the perimeter stays put, and no amount of perimeter piering will touch it. Slab piers are installed through the floor slab itself: the concrete is opened at each location, a pier is driven or screwed to bearing, and the slab section is supported and patched.
It is the most disruptive of the three because it happens inside the house, and it is the one that most often surprises homeowners who were expecting an exterior job.
Bell bottom piers, and older Colorado practice
Drilled concrete piers with a flared base, sometimes called bell bottom piers, appear in older Colorado foundation work and are still specified where drilling is more practical than driving. They spread load over a wide base rather than reaching a deep bearing stratum, and they behave differently from a driven steel pier in expansive soil. If a quote proposes them, it is worth understanding why that choice was made for your site.
How pier count is decided
Not by the length of the crack. Pier spacing follows the load path: piers go where the structure delivers load into the footing, which means at corners, under bearing points, and at intervals along a wall determined by wall construction and load. Typical residential spacing runs somewhere between five and eight feet, tightening under concentrated loads.
The practical implication is that a quote proposing the same pier count for any house of a given size is not a quote that was engineered. The elevation survey and the load path together determine the number, and both should be visible in the paperwork.
Reading depth on a quote
No one knows depth to bearing on a Grand Valley lot until the first pier goes down. Depth varies within a single street, because the alluvium over Mancos Shale is not laid down uniformly. A properly written quote therefore states three things:
- The assumed pier depth the price is built on.
- The price per additional foot beyond that assumption.
- Whether the assumption is a firm cap or an estimate.
That third point is where quotes diverge most and where a total moves after work has started. It is a fair thing to ask about before signing anything, and any contractor pricing this work every week will have a straightforward answer.
What piers cost here
Installed pricing in the Grand Valley runs roughly $1,400 to $2,600 per pier, with the spread driven by pier type, depth, and access. Most residential jobs need 6 to 16 piers. The cost calculator lets you set a count and see the range, and the cost guide covers what else lands on the invoice.
Related: settlement repair scope and how to read the quote itself.