Multiply length by width for each rectangular section, then add the sections together. Nothing fancier is needed — break odd shapes into rough rectangles and don't sweat a foot here or there; bulk material math forgives estimates.
Quick field method
- Pace it off — one relaxed stride is about 3 feet, so a 10-pace bed is roughly 30 ft long
- Length × width per section — a 30 × 4 bed = 120 sq ft
- Add them up — three beds like that = 360 sq ft
- Convert to yards — square feet × depth in inches ÷ 324, rounded up to the next half yard
From there the material calculator does the conversion for any material and depth — measure once in the morning and your delivery can be booked by lunch.
