Foundations for pre-engineered steel buildings
A pre-engineered steel building is only as good as what it's bolted to. Our primary frames generate concentrated vertical, horizontal, and uplift loads at each column base. Your foundation has to resist without differential settlement, frost heave, or slab cracking.
We supply the anchor-bolt plan, the column reactions, and the design loads. Your civil engineer or qualified GC designs and pours the foundation itself. This page walks through the three foundation types we design to, what we provide, and what to expect from your contractor.
Three foundation types we engineer to
- 01
Slab-on-grade with thickened edges
A single concrete pour with a perimeter grade beam that doubles as the column footing. Fastest and cheapest for warm-climate and heated-slab applications. Limited by frost depth; below the frost line, you need frost-protected detailing or a separate footing.
- 02
Perimeter wall (continuous footing)
Continuous strip footing and stem wall around the perimeter, slab poured separately inside. The default for most of Canada: frost depth is met, anchor bolts embed into the wall, and the slab is independent of the structure. Works for any heated or unheated building.
- 03
Pier and grade beam (isolated footings)
Individual pad or drilled-pier footings at each column location, with a non-structural slab on fill or grade beams between. Used when soil is poor, frost depth is deep (MB/SK/NT), or the interior slab is loaded heavily (heavy equipment, cranes) and needs to be isolated.
What loads will your foundation see?
Every project gets a set of column reactions: the vertical, horizontal (shear), and uplift (wind) forces at each column base. These are the primary input for your foundation engineer. Typical ranges for a clear-span rigid-frame building:
Typical column reactions at base (per column pair)
| Width | Vertical (D+S) | Horizontal (wind) | Uplift |
|---|---|---|---|
| 40' span | 15–25 kip | 4–8 kip | 3–6 kip |
| 60' span | 25–45 kip | 8–14 kip | 5–10 kip |
| 80' span | 45–70 kip | 14–22 kip | 10–18 kip |
| 100' span | 70–110 kip | 22–35 kip | 18–28 kip |
| 150' span | 110–180 kip | 35–55 kip | 28–45 kip |
We provide full reactions up-front
Once your design is confirmed, we issue an anchor-bolt plan with reactions at each column. Your foundation engineer designs to these. No guessing, no coordination delays.
Anchor bolts and embedment
We ship every anchor bolt required (typically 3/4", 7/8", or 1" diameter ASTM F1554 grade 36 or 55) with leveling nuts, top nuts, washers, and a templating jig to keep the bolt pattern square while concrete is poured.
Embedment depth is set by the pull-out capacity required to resist uplift and shear. For most buildings, 12" to 18" embedment into 25-MPa concrete is sufficient. Bolts are cast-in-place; epoxied post-installed bolts are a fallback for remediation only.
- 01
Keep bolts vertical
The single most common field error is crooked anchor bolts. Use the template we supply, double-check plumb before and during the pour, and vibrate carefully around each bolt cluster.
- 02
Protect bolts during the pour
Cap every anchor bolt before concrete hits it. Thread damage is a rework nightmare; you cannot just "clean up" a few thousand PSI of concrete out of an M24 thread.
- 03
Verify elevations
Top-of-concrete elevation must be within ±1/4" across the whole footprint. Small variations compound into big problems when girts and eave struts don't meet their bearing surfaces.
- 04
Grout after erection
Columns sit on leveling nuts with a gap. After erection and plumb, non-shrink grout gets pumped or poured between the base plate and top of concrete. Do not grout before erection.
What we supply vs what your GC pours
| Scope item | Hybrid Steel | Your contractor |
|---|---|---|
| Column reactions & design loads | Yes | — |
| Anchor-bolt plan (PDF + DWG) | Yes | — |
| Anchor bolts, nuts, washers, template | Ships with building | — |
| Geotechnical report | — | Owner / GC |
| Foundation engineering stamp | — | Local civil engineer |
| Excavation, forming, rebar | — | GC |
| Concrete pour and finish | — | GC |
| Setting anchor bolts in formwork | — | GC (per our plan) |
| Non-shrink grout at column bases | — | GC (post-erection) |
No geotechnical report yet?
For preliminary quoting, soil assumptions are fine. But before your final foundation design, get a geotechnical report from a local firm, with 2 boreholes minimum for most footprints. It pays for itself in risk avoided.
Ready to spec your building?
We'll scope the structure, recommend the right envelope, and send a line-item quote.