Interior foundation drainage plane
Question for the experts. I’ve been thinking about the ramifications of installing rigid or spray foam insulation directly to the interior foundation wall of a basement. Over the past 15 years I have built approx. 60 custom homes and I can think of 5 foundations that developed some type of leak after construction was complete. All leaks were easily fixed from the interior side. Two were tie leaks and three were hairline foundation cracks. One of the tie leaks showed up when a customer installed a lawn sprinkler system and a sprinkler head soaked a planting bed along the foundation wall.
Any type of foam insulation applied directly to an interior foundation wall will mask the effect of a leak. It seems like some sort of drainage plane would be a good idea to allow water from a leak to drain and the possibility of a leak to be discovered. Thoughts? Would a drainage plane cause other problems (ie. air sealing)?
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