Is water migration through deck grade beams into slab a concern?
Hi my name is Owen,
We are working on a project in SF bay area, zone 3 and we are in the process of digging grade beams for a slab on grade foundation. I have read articles on GBA and seen details for water proofing a slab on grade with drainage and vapor barrier wrapped up side walls of slab.
We have exterior uncovered deck grade beams that extend from our houses’ mat slab and will support a wood deck. I am not clear if I need to be concerned about water migration from these deck grade beams in the winter when it rains. We have wood flooring inside so we don’t want a moist slab.
We are on soil that is subject to settlement so the grade beams of deck are 18’x18″ and there are around 20 connections to the house mat slab, to give a sense of the area that deck grade beams are connecting with house slab.
Is this situation a concern?
Also There are a few small slab extensions to the exterior that are covered in stone, or by decking, should these have some membrane or sealant over them?
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