Disclaimer

Last updated: 26 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 Australian retail/trade rates at the time of publication. Actual prices vary by state and territory, supplier, quantity discounts, and market conditions, and are shown exclusive of GST unless stated. Always get written quotes.
• No structural advice. Calculators that touch beams, lintels, footings, slabs, loads, fall/gradient, drainage, electrics, gas, or heating/cooling sizing are screening tools only. Designs that affect structural integrity, safety, or National Construction Code (NCC) compliance must be signed off by a qualified professional — a chartered structural engineer, registered architect, licensed builder, licensed gasfitter, licensed electrician, or comparable competent person as required by law.
• NCC, Australian Standards & planning. Many works require building approval, a development application (DA), an owner-builder permit, or compliance with the National Construction Code and the relevant Australian Standards (AS/NZS). In bushfire-prone areas a Bushfire Attack Level (BAL) assessment under AS 3959 may apply. This site does not determine whether any specific works require consent — that is the owner's or contractor's legal responsibility, and requirements vary between states and territories.
• 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 (Australia)

Nothing in this disclaimer limits or excludes any rights or guarantees you have under the Australian Consumer Law (Schedule 2 of the Competition and Consumer Act 2010) 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 hot-water work (licensed trades only).
• Works near a boundary, easement, or heritage-listed property.
• Drainage that discharges to a public sewer or stormwater system.
• Building in a bushfire-prone, flood, or termite-management area.
• Anything involving asbestos, lead paint, or other regulated materials.

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