Disclaimer

Last updated: 20 April 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.