Feature
Why You Order More Than You Measured
Errol Nakamura · · 2 min
Measured area is not order quantity. Every material has a waste factor, and the reason to respect it is rarely the material cost — it is that a second order arrives late, and sometimes visibly different.
Where the waste actually goes
Cuts. Any run that does not divide evenly into the material leaves an offcut, and offcuts are only reusable if the piece is long enough and unpatterned. A room with many corners wastes more than a large square one at identical area.
Breakage. Tile and slate break in transit and on the cut. Some of that is unavoidable.
Pattern repeat. Anything with a directional or repeating pattern must be aligned across joints, and alignment is paid for in offcuts. Diagonal layouts cost more again.
Defects. Boards warp, tiles vary, timber has knots in the wrong place. Some proportion of what arrives is not usable where you wanted it.
Typical starting points
Roughly 10% for straightforward tile on a simple rectangular floor, and more like 15% once the layout is diagonal, patterned, or the room is complex. Flooring and cladding sit in a similar band. Long straight runs of plain material sit lower.
Treat these as starting points to sanity-check a supplier’s figure, not as specification — the right number depends on the layout in front of you.
The reason it is not just about money
Dye lot and batch. Tiles, engineered flooring, brick and paint are manufactured in batches, and batches differ slightly in colour. Within a batch the variation is controlled; across batches it may not be.
That is why the advice is to order the whole job in one batch and keep the surplus. A top-up order weeks later can be a visible mismatch on the same wall — a defect no amount of skill installs away.
Keep the offcuts
Enough for a repair, in the same batch, stored flat and dry. The alternative, years later, is matching against a discontinued line.
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