In order to take into account an increase in moisture content it is necessary to incorporate an expansion gap. For Tongue & Groove boards a gap should be provided around the perimeter of the floor to any up stands or abutting construction to allow for possible expansion of the decking. This should be a minimum of 10mm at each edge of 2mm per metre run of board. Larger floors, above 10m in length, may also need intermediate expansion gaps. The gaps should either be left open and covered by a skirting board or filled with a compressible silicone product. For further information please refer to the EGGER Advanced Structural Flooring System.