This approach keeps irregular geometry auditable. Measure rectangles, triangles and circles separately, then enter each section’s area rather than guessing one average length and width.

01 / Formula

How this is calculated

Cubic yards = (section 1 + section 2 + section 3) × depth in ÷ 324

02 / Assumptions

What the estimate assumes

  • Each entered section area is measured independently.
  • Sections do not overlap.
  • Depth is uniform across the combined bed.

03 / Worked example

See the math in context

Sections of 120, 85 and 45 sq ft total 250 sq ft; at 3 inches deep that equals 2.31 cubic yards before allowance.

04 / Guidance

Avoid overlapping sections

Sketch boundaries and assign every part of the bed to one shape. Where shapes overlap, subtract the shared area once.

Questions

Frequently asked

How do I measure an irregular area?+

Split the bed or lawn into rectangles, circles, and triangles, calculate each area, then add them. Measure narrow curves in shorter sections for a better approximation.

Should I include extra material?+

Use a visible allowance for grade variation, settlement, compaction, spillage, cuts, or future repair as appropriate. The right percentage depends on the material and site.