Foundation Calculator
Slab Foundation
Calculate concrete for a monolithic or stem-wall slab foundation
Basement Foundation Walls
Calculate concrete for poured basement foundation walls
Formula
Slab = L × W × Thickness/12 | Wall = Perimeter × Height × Thickness/12 | Footing = Perimeter × Width/12 × Depth/12 | Cu Yd = Cu Ft / 27
Frequently Asked Questions
How thick should a house foundation be?
Slab: 4" thick with thickened edges of 12". Basement walls: 8" minimum (10" for tall walls or heavy loads). Footings: typically 8" deep and 20" wide for residential. Always consult local building codes and a structural engineer.
What type of foundation do I need?
Slab-on-grade: Warm climates, flat lots, budget-friendly. Crawl space: Moderate climates, sloped lots, access to plumbing. Basement: Cold climates (footing below frost line anyway), adds living space. Pier/post: Flood zones, steep slopes, minimal footprint.
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