Question (WOODWEB Member) :
I am scheduled to install red balau decking on a deck in a high humidity area. I have heard that it may cup if installed on a deck closer than 18" to the ground. Does anyone have information on this? Is there any difference between red and yellow balau for this application?
From Professor Gene Wengert, Sawing and Drying Forum technical advisor:
There are five groupings within the Shorea or Philippine mahogany group of SE Asian tropical wood - dark red meranti, light red meranti, white meranti, yellow meranti and balau. The balau wood is certainly dense and quickly dulls cutters. Allergic reactions are common. It will cup when the bottom side is more humid than the top, as will other species of high density. Hence, keeping a large air space underneath the deck that is ventilated is desirable.