Estimates only
The calculators give geometry and material estimates. Results can be wrong because of rounding, measuring errors, product differences or mistakes in our maths. Check every number before you cut or order.
Not professional advice
Nothing on this site is engineering, architectural, legal or building-code advice. "Meets" on a check means a result meets the specific IRC 2021 figures we list, not that a design is approved, safe or code-compliant where you live. Local codes and adopted editions differ. Stairs, decks, rafters and roofs are structural: check your local code, get the permits and inspections your area requires, and consult a licensed builder, engineer or roofer.
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The site is provided "as is" without warranties of any kind. To the extent the law allows, we aren't liable for any loss or damage from using it.
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