Plan it once, buy it right

Guides

How to get an accurate estimate

Start by measuring carefully. Most projects come down to length times width, and our guide to measuring square footage covers odd shapes. For materials sold by volume, such as mulch, topsoil, gravel and concrete, you also need a depth. Cubic yards explained shows how bags, bulk and tons relate.

Each calculator includes a waste allowance with a sensible default for that material, a Show the math button so you can check every step, and a worked example. Round up when you order. Running short in the middle of a job almost always costs more than a few leftovers.

The results are estimates for planning and comparing quotes. Check quantities with your supplier, and check permits and local codes for decks, fences and roofs.