How to waterproof foundation walls pinned to rock
The foundation walls have been poured on my project on a rocky sloped site. I ended up having to pin the walls directly to the rock (geotech’s requirement) so there are no footings anywhere. There will be an unvented conditioned crawlspace which will be below grade on the uphill side, and above grade on the downhill side. The wall on the uphill side is about 8ft tall and the crawlspace slab will sit about 5 feet from the top of the wall, so at least a couple of feet above the sub grade. For the waterproofing strategy, I was planning on using an elastomeric fluid applied coating all the way around, with dimple mat on the uphill side. The walls were scribed to the undulating surface of the rock so I’m wondering how best to install the dimple mat? Rough scribe it or try to transition it from vertical to horizontal at the base of the wall? Do the details really matter so long as bulk water can’t sit above the slab level of the crawlspace walls? The perimeter drainage will near the base of the wall but will be above some of the low points in the rock. The crawlspace wall vapour barrier will be 4 inch EPS (Craiglist score), sub slab will be 4 inch PES and poly.
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