Question 1

How much waste should I add?

Accepted Answer

About 10% for straight layouts and roughly 15% for diagonal or patterned layouts; large-format or fragile tiles may need more.

Question 2

Does joint width change the number of tiles?

Accepted Answer

Slightly. Wider joints make each tile's footprint bigger, so fewer tiles are needed, but much more grout.

Question 3

What joint width should I use?

Accepted Answer

It depends on the tile type and the manufacturer's recommendation; rectified tiles allow narrower joints than tiles with less regular edges.

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