Garage Foundations Alberta

We Pour According to Code, Not to Guesswork

At Marshall Construction, we do not eyeball depths or ballpark mixes. Every garage foundation begins with a soil probe and a reading of the National Building Code – 2023 Alberta Edition. The code calls for footings that sit on soil bearing at least 75 kPa, concrete that reaches 15 MPa before backfill and reinforcing steel with a 400 MPa yield. We verify those numbers on our batch tickets before the first wheelbarrow tips. If the site shows softer clay we either dig to competent soil or switch to engineered screw piles, never hoping frost will spare a thin slab.

Materials we trust on every slab

Our mix design for detached and attached garages in Central Alberta is a 25 MPa air-entrained concrete with 5 to 8 percent entrained air and 19 mm aggregate. Running a stronger mix than the minimum keeps shrinkage cracks tight and lets us finish sooner in cool shoulder seasons. Where clients want insulated concrete form (ICF) stem walls we use Type 2 expanded polystyrene blocks that comply with CAN/ULC-S701.1, then pump a slump-controlled mix that fills every web without segregation. That same attention extends to vapour control—under-slab poly is taped tight up the wall, and 100 mm of high-density insulation isolates the slab from frost heave so radiant tubing can work efficiently.

For wider pours we roll out our Telebelt conveyor so the stone lands gently at the far edge of the form instead of bouncing through fresh mud near the truck chute. Fewer re-handles mean flatter finishes and no dislodged rebar.

Placement that resists frost and heave

A garage might weigh less than the main house, but it still sees the same soil cycles. We cut footings at or below 3.9ft to clear the frost line and place two continuous 15 M bars 2.9" above the bottom of the footing. Dowels rise 23.6" on centre to tie the wall or thickened slab edge, creating the top and bottom lateral support the code demands. Before any wall is backfilled, we secure anchor bolts or embedded straps so the wall cannot bow outward under wet spring soils.

Slab-on-grade sections get a thickened apron under overhead doors to control curling. We pour the slab monolithically with the perimeter beam to lock everything together, then saw-cut the surface as soon as it holds foot traffic. Those cuts follow the four-metre rule—panels no larger than 13ft by 13ft—to keep shrinkage cracks orderly.

Because Alberta’s chinook swings can shock-cool fresh concrete, every winter pour wears an insulated blanket rated at R-7.7. We monitor internal temperature with probes and refuse to strip forms until the core tops 10 °C for three consecutive days. It is an extra step but nothing ruins a new garage faster than early-age freeze-thaw damage.

Our foremen keep a weather eye on hydrostatic pressure too. If the lot sits low we install a perforated perimeter drain and daylight it or tie it to a sump. High water tables account for nearly half of the slab repairs we are called to fix; prevention at the foundation stage is cheaper than epoxy injection after the fact.

Looking for Garage Foundation Support?

Every inspection ends with the municipal officer signing off on depth, rebar, anchor placement and concrete strength. We hand you that paperwork along with cylinder break reports so resale appraisers never question the slab’s capacity.

We build garage foundations Alberta residents can rely on. Need an expert crew that lives code-compliance and safety on every pour? Call Marshall Construction for a site visit in Red Deer, Lacombe or Sylvan Lake today and lock in a foundation that lasts.