About Home Build Math

Home Build Math is a small, independent site of calculators for home and yard projects. It is built and maintained by a computer engineer who writes and tests each calculator.

How the calculators are checked

• Each formula is implemented twice, independently, and the two versions are compared with automated tests.
• Building-code limits (for example stair riser and tread limits) are quoted from the code text, with the edition and section named on the page.
• Material constants (for example aggregate density or paint coverage) come from a named public source. Where no reliable source exists, the calculator asks you for the value instead of guessing.

More detail, including every source and how results are rounded: How we check.

Limits

Results are estimates. Local building codes, site conditions and product specifications differ. For structural work, follow your local code and consult a qualified professional.