Disclaimer

These are estimating tools

Every calculator on this site converts dimensions and material properties into quantities. That is all they do. They do not size structural members, verify a design, assess bearing capacity, check load paths, or confirm compliance with any building code or standard.

Results depend on your inputs

Many results here are directly proportional to a material property such as density, coverage rate or mix ratio. Default values shown on the site are typical planning figures, clearly labelled as such and editable in every case. They are not correct values for your project. Use the figures from your mix design, laboratory results, supplier data sheets or project specification.

Local standards take precedence

Construction practice, terminology and required allowances vary between countries and between projects. Where anything on this site conflicts with your project specification or the codes that apply in your jurisdiction, your specification and local codes govern.

Verify before you order or build

Check every quantity independently before placing an order or proceeding with work. A calculator cannot see your drawings, your ground conditions, or the parts of the job that do not fit a simple rectangular shape.

Professional engineering

Where a project requires structural design, temporary works design, or any other professional engineering input, engage a qualified engineer licensed in your jurisdiction. Nothing on this site is a substitute for that.