Tile Waste Percentage: Pattern, Cuts and Spare Boxes

Measure the surfaces and consider perimeter cuts, diagonal or herringbone patterns, openings, breakage, selection defects and replacement stock. Large tiles in small irregular rooms can produce difficult offcuts. Different materials or dye lots should remain separate orders.

Do not claim TCNA or ANSI establishes a generic 10% waste requirement. Those publications concern installation criteria and methods. A manufacturer purchasing recommendation, if applicable, must be identified as product-specific guidance.

For 100 ft² with a chosen 10% allowance and 1 ft² tile faces, required tiles = ceil(110 / 1) = 110. If the box contains twelve tiles, boxes = ceil(110 / 12) = ten, supplying 120 tiles. The ten extra tiles beyond the planned requirement come from package rounding.

Do not lower the area purchase requirement because grout joints occupy part of the installed surface. Joint geometry belongs in layout and grout calculations, while purchasing remains a conservative tile face-area takeoff.

Inspect balanced-edge and centered layouts for slivers before buying. A higher allowance does not make an impractical sliver easier to install. Check whether offcuts can be reused with the required orientation and finished edges; do not assume every cut is recoverable. Keep spare material labeled by product, size and lot for future repairs.