PreConstruct AIFree calculator
ICF calculator — forms and concrete
Type the wall length and height, the openings and corners, and the concrete core the drawings show. Get the forms, straight and corner, and the concrete to order — with the working.
Concrete to order
27 CY
26.83 CY · 20.52 m³
Forms
272
244 straight + 28 corner
Wall area
1,380 SF
128.21 m²
Courses
7
The working
- wall 160 ft × 9 ft − openings 60 SF = 1,380 SF
- forms 1,380 SF ÷ 5.33 SF × waste of 5 per cent = 272
- courses 9 ft × 12 ÷ 16" = 7; corners 4 × 7 = 28 corner forms
- concrete 1,380 SF × 6" ÷ 12 = 690 ft³ ÷ 27 × waste of 5 per cent = 26.83 CY → order 27
A starting figure, not an engineered quantity. Sizes, reinforcing and code requirements come from your drawings, your specifications and your engineer — check them before you order.
Where a calculator stops
This does one run, from numbers you type. A bid is every run on every sheet.
- — It doesn't read the drawing set or its schedules
- — It doesn't measure on the PDF or keep the lengths
- — It doesn't show what an addendum changed
- — It doesn't price, add labour or build a proposal
Forms
A 48 × 16 in form covers 5.33 SF of wall: (L × H − openings) ÷ 5.33, plus waste. Corners take one corner form a course, and there are height × 12 ÷ 16 courses; they are counted inside the total. Form sizes vary by maker, so the face and height are yours to change.
Concrete
Wall area × core thickness: SF × core in ÷ 12 ÷ 27 = CY. A 6 in core takes 0.5 ft³ a square foot — about 54 SF a yard; an 8 in core, about 40 SF a yard. Add waste, then round up to the half yard for the order.
What the drawings decide
Core thickness, reinforcing, and the height you can pour in one lift come from the structural drawings and the form maker. This counts forms and measures concrete from what they show.
Questions estimators ask
- How much concrete per square foot of ICF wall?
- 0.5 cubic feet for a 6 in core, 0.67 for 8 in, 0.83 for 10 in. Divide by 27 for cubic yards — a 6 in core fills about 54 SF a yard.
- How many ICF blocks per square foot?
- A standard 48 × 16 in form covers 5.33 SF, so about 0.19 forms per square foot before corners and waste. Check your form maker's dimensions.
- How do I count ICF corner blocks?
- One corner form per course at each corner. Courses are the wall height in inches divided by the form height, rounded up.
- What core size do I need?
- The structural drawings specify it. This calculator measures concrete for the core you type; it does not choose one.
Stop retyping sizes into a calculator
On PreConstruct AI you measure on the PDF, type the sizes the drawings print, and the concrete, forms, bars, board and stringers come out with the arithmetic beside every line — in imperial, metric or both. Your first bid is free, with no card.