What Is an Expansion Gap?

An expansion gap is the space deliberately left between a floor and the walls around it, so the material can expand and contract with temperature and humidity without pushing against anything.

What happens without one

The floor grows, has nowhere to go, and lifts. Boards peak in the middle of the room, edges rise, and laminate joints separate.

It is one of the most common flooring failures and it is entirely preventable. It also usually appears months later, with the first significant seasonal change, long after the fitter has been paid.

Where it hides

The gap is covered by skirting, beading or a threshold strip, so a correctly fitted floor looks as though it runs right to the wall.

That means you cannot check it after the event without lifting an edge, which is another reason to hold a final payment until the floor has been through some use.

Related: acclimatisation

Wood and laminate should sit in the room, in normal conditions, before fitting, acclimatisation. A floor fitted straight off the van will move more afterwards, and an expansion gap sized for a stable material may not be enough.

Ask how long the fitter allows.