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Concrete block calculator.
Wall length and height in, block count and core fill out. Take off the doors and windows and pick your block width.
Pricing the whole job?
ConCal takes the slab, footings, steel and labor from one drawing and turns them into a bid your customer can sign.
How to figure block for a wall
A standard 8 by 8 by 16 block covers 16 inches by 8 inches of wall, mortar joint included. That is 0.889 square feet, so it takes 1.125 blocks to cover one square foot. Six and twelve inch block have the same face size, so the count works the same way.
Blocks = (length × height − doors and windows) × 1.125
Worked example. A 40 foot wall, 8 feet tall, with one 3 by 7 door. That is 320 square feet, less 21 for the door, or 299 square feet. 299 × 1.125 = 336.4, so 337 blocks. Add 5% for broken and cut block and order 354.
Eight feet of wall is 12 courses. Each foot of wall length takes 0.75 of a block per course, so an 8 foot wall takes 9 blocks for every foot of length. Handy for a quick check on site.
Filling the cores
Fully grouted 8 inch block takes roughly 0.26 cubic feet of grout per square foot of wall. The 299 square foot wall above is about 78 cubic feet, or 2.9 yards before waste. Twelve inch block takes a little under twice that. Many walls only fill the cores with rebar in them, so set the fill percent to match the plan.
The footing under the wall is its own pour. Figure it with the footing calculator.