The importance of the expansion joint should not be underestimated. The expansion joint should be 10mm, which must be left along each wall. This free space prevents warping, which causes boards along walls or at the centre of the flooring to bulge.
Special attention must be paid when installing the first and last row of boards in order not to impede the function of the expansion joint. Care must also be taken to avoid anchoring, as that will completely hamper the movement of the boards, otherwise expansion joints are useless.