What is the shrinkage rating per board?
We recommend, if it’s cold out (below 4ÂșC), 3mm gap end to end; if it’s hot, no gap. Other than that use a 1.5mm end to end. See our installation instructions to see how to back cut and see no gap. ECO CorrectDeck expands and contracts less than other brands of composite decking. There is no width shrinkage or expansion.