A diagonal floor is laid exactly like a straight floor, but the rows run at 45° to the walls. The eye follows the longest line in the room, the diagonal, so the space feels larger.
What changes
- Reference line: you cannot follow a wall. Snap a chalk line at 45° from your start corner, using a 3-4-5 triangle or a large square.
- Cuts: almost every edge piece is cut at an angle. The planner gives the length of both long edges so you only mark two points and join them.
- Waste: angled offcuts are harder to reuse. Plan for 10–15% extra.
- Time: expect the job to take about 1.5 times as long as a straight lay.
Tips
- Cut a few test pieces to check your 45° setting before cutting into full planks.
- A mitre saw set at 45° makes repeatable cuts; mark the edge lengths anyway, because walls are rarely exactly square.
- Where the floor meets another room, a straight transition profile looks neater than continuing the diagonal through the doorway.