In a third offset, row two starts a third of a length further along than row one, row three another third, and then the pattern repeats. It forms gentle diagonal steps across the floor.
Why tile installers prefer it
Large porcelain tiles are never perfectly flat; most have a small bow. The industry guideline for tiles with a side longer than about 45 cm (18 inches) is an offset of 33% or less, unless the manufacturer says otherwise. With the joint a third along, the bow lines up better from tile to tile.
Look
A third offset reads as more relaxed than brick, but more structured than random stagger. With wood-look tile planks it gives a convincing floorboard look without the risk of joints lining up.
Tips
- Mark the offset on a long batten: zero, one third, two thirds. Use it to check every row start.
- Watch for diagonal staircase lines in large rooms; vary the start slightly if they become distracting.
- Use levelling clips on large formats.
Waste
About 7–10% for tiles, including breakage.