Foundation Cost Estimator

Price the part of the building you'll never see again. Pick a foundation type and structure size — get concrete volume, granular base tonnage, and an itemized 2026 cost estimate with editable prices. Not sure which type? The slab vs frost wall guide resolves that decision first.

Structure & Foundation

Foundation Type

The standard for detached garages on drained sites.

Length (ft)

Width (ft)

Slab thickness

Granular base depth

Adjust unit prices (CAD, editable)

Concrete, delivered ($/m³)

Forming, placing & finishing ($/sq ft)

Contractor labour for slab work. Set lower if DIY.

Mesh / rebar allowance ($/sq ft)

Granular, delivered ($/tonne)

Frost wall, formed ($/lin ft per ft of depth)

Includes excavation, forming, concrete, backfill.

Per pier, installed ($)

Wood floor system ($/sq ft)

PT skids, joists, sheathing — materials + modest labour.

Estimated foundation cost

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Quantities & Cost Breakdown

Item	Quantity	Cost

Refine the rest of the build: price the granular base order in the Fill & Gravel Calculator, the walls in the Wall Framing Calculator, the roof in the Roof Cost Estimator — or get the whole-building ballpark in the Garage Cost Calculator.

Disclaimer: This is a planning-level quantity and cost estimate using typical assumptions (thickened-edge floating slab, standard forming). It is not a structural design — slab thickness, reinforcement, frost depth, and pier sizing are set by your soil, your provincial code, and your permit drawings. Piers exclude beams and floor framing. Confirm with your building department and local contractors.

How this estimate works

Slab: concrete volume = area × thickness (+10% waste), granular base = area × depth × 1.8 t/m³ with compaction allowance, plus mesh/rebar and forming/finishing labour at your editable rates. Frost wall adds perimeter × depth × the formed-wall rate to a standard slab. Piers: perimeter ÷ spacing, at your per-pier installed price. Wood floating floor prices the PT skid-and-joist system per square foot — common for sheds under ~160 sq ft where code permits (see the permits guide). The result is shown ±15%.