A.John Leeke, a preservation consultant from Portland, Maine, responds: The drainage off the deck will definitely be better if the boards run from the house down the slope toward the edge of the porch. I usually slope my porch decks about 1/4 or 3/8 inch per foot. I’ve found that 1/8 inch per foot is not enough to get the water moving off the porch.
If you are concerned about end checks developing in the exposed end grain of the deck boards, I suggest treating the end grain of the boards with penetrating epoxy consolidant before any other finish is applied. This seals the end grain, limiting the movement of water in and out and minimizing checks.
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