Disclaimer

Last updated: 24 June 2026

BuildMetricLab provides free online construction calculators, material estimators, and unit converters. The results they produce are estimates for educational and planning purposes only. They are not, and must not be treated as, professional advice.

What this means in practice

• Quantities are estimates. Every real-world build has site-specific conditions (wastage, cut-offs, substrate, access) that change what you actually need. Verify every quantity with your supplier or trade contractor before ordering. We recommend building in additional contingency on top of the wastage assumptions shown.
• Costs are illustrative. Prices shown in the calculators are based on typical UK retail/trade rates at the time of publication. Actual prices vary by region, supplier, quantity discounts, and market conditions. Always get written quotes.
• No structural advice. Calculators that touch beams, lintels, foundations, loads, fall/gradient, drainage, electrics, gas, or boiler sizing are screening tools only. Designs that affect structural integrity, safety, or Building Regulations compliance must be signed off by a qualified professional — a chartered structural engineer, registered architect, Gas Safe engineer, NICEIC-registered electrician, or comparable competent person as required by law.
• Building Regulations & planning. Many works require Building Regulations approval, planning permission, a Party Wall notice, Competent Person Scheme certification, or similar. This site does not determine whether any specific works require consent — that is the homeowner's or contractor's legal responsibility.
• No warranty. Calculators are provided "as is". Formulas are documented on each tool page so you can check the method. We test actively but cannot guarantee every edge case. Use of this site is at your own risk.

Consumer rights (UK)

Nothing in this disclaimer limits your statutory rights under the Consumer Rights Act 2015 where those rights cannot be excluded by contract.

When to consult a professional

Always consult a suitably qualified professional before:

• Any structural alteration (removing walls, cutting joists, new openings, steel beams).
• Gas, electrical, or unvented hot-water work.
• Works near a boundary, party wall, or listed/conservation area property.
• Drainage that discharges to a public sewer or watercourse.
• Anything involving asbestos, lead paint, or other regulated materials.

If in doubt, don't. Get a professional.