Estimate CMU blocks, mortar, rebar, grout, and footing concrete for any foundation — from crawl spaces to full basements. Enter your building footprint and get instant results.
Crawl Space
Stem Wall
Full Basement
Garage Frost Wall
Commercial
| Foundation Type | Typical Height | Courses | Block Width | Reinforcement |
|---|---|---|---|---|
| Crawl Space | 2–4 ft | 3–6 | 8" or 10" | Vertical every 48" |
| Stem Wall | 1–3 ft | 2–4 | 8" | Vertical every 48" |
| Full Basement | 8 ft | 12 | 10" or 12" | Vertical every 32" |
| Garage Frost Wall | 1–2 ft | 2–3 | 8" | Minimal |
| Commercial | 8–12 ft | 12–18 | 12" | Engineered plan |
Foundation walls wrap around the full perimeter of your building. Unlike single-wall projects, foundation estimation starts with the building footprint (length × width) to calculate the total linear footage of wall needed.
Record your building's length and width in feet. The calculator computes the perimeter automatically (2L + 2W).
Foundation height depends on type: 2–4 ft for crawl spaces, 8 ft for basements. Measure from footing top to sill plate.
8" blocks for standard residential, 10" for deeper crawl spaces, 12" for basements and commercial foundations.
Perimeter × height ÷ 0.89 sq ft per block = base count. Add 10% waste for cuts and corners.
Foundation walls require vertical rebar every 32–48" and horizontal bond beams. All cores should be grouted.
Concrete footings (typically 16" wide × 8" deep) run the full perimeter. Our calculator estimates this automatically.
Each foundation type has unique requirements for block width, reinforcement, and waterproofing.
The most common residential foundation. 2–4 ft walls create a ventilated space below the floor. Requires moisture barriers and proper ventilation.
Short walls (1–3 ft) that raise the building above grade. Common in warm climates where deep frost lines aren't a concern.
8 ft foundation walls creating a full below-grade living or storage space. Requires 10" or 12" blocks, waterproofing, and engineered drainage.
Shallow perimeter walls (1–2 ft) that extend below the frost line to support a concrete slab. Minimal reinforcement needed.
Foundation block width affects structural capacity, insulation value, and cost. Here is a comparison:
8-inch CMU
10-inch CMU
12-inch CMU
| Block Width | Best For | Weight | Core Volume | Cost/Block |
|---|---|---|---|---|
| 8-inch | Stem walls, crawl spaces, garages | 38 lbs | 0.22 cu ft | $1.50–$2.50 |
| 10-inch | Deep crawl spaces, light residential | 43 lbs | 0.28 cu ft | $2.50–$3.50 |
| 12-inch | Full basements, commercial, tall walls | 55 lbs | 0.35 cu ft | $3.50–$5.00 |
Foundation work requires professional engineering
Foundation design must account for soil bearing capacity, frost depth, water table, and building loads. Always consult a structural engineer and obtain permits before starting foundation construction.