How to measure for any project
Almost every material estimate starts from the same place: an accurate area or volume. Get the measuring right and the calculators do the rest. Here's the method that works across paint, tile, flooring and concrete.
Measuring area (paint, tile, flooring)
Area is length × width. For walls, it's perimeter × height. Measure to the nearest half-foot or 10 cm — the waste factor absorbs small rounding. For irregular rooms, break the space into rectangles, measure each, and add them together.
Measuring volume (concrete, gravel, mulch, topsoil)
Volume is length × width × depth. The classic mistake is mixing units: depth is usually in inches or centimetres while length and width are in feet or metres, so convert depth to the same unit first. Our concrete calculator does this automatically.
How much waste to add
| Project | Typical waste |
|---|---|
| Paint | 10% (for touch-ups and a second coat) |
| Tile / flooring, straight lay | 10% |
| Tile / flooring, diagonal | 15% |
| Herringbone / chevron | 15–20% |
| Concrete | 5–10% overage |
| Roofing, drywall | 10–15% |
Tools you'll want
- A 25 ft tape measure or a laser measure for speed and accuracy.
- A notepad — sketch the room and write each measurement on the relevant wall.
- A calculator (you're in the right place) to convert measurements into materials.
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