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Foundation wall below-grade exterior waterproofing: Builder questions wisdom – GreenBuildingAdvisor
- June 14, 2025
- Posted by: wendy
- Category: Uncategorized
For my new home build I’m spec’ing waterproofing of below-grade foundation walls with something like Tremco Tuff-N-Dri.
That’s based on reading as much as I could find about this topic, including the following:
https://www.greenbuildingadvisor.com/article/dampproofing-and-waterproofing-foundation-walls
https://www.jlconline.com/how-to/foundations/foundation-waterproofing-that-works_o
Based on my understanding from those and other sources, waterproofing (rather than merely dampproofing with asphaltic goo) is important in order to span inevitable cracks and resist hydrostatic pressure.
However, the builder says that waterproofing the exterior will drive water from the curing concrete to the interior for up to one year, and therefore asphaltic goo is a wiser choice.
I’ve also seen this idea expressed elsewhere. For example, the “Solutions Guide” available as a PDF from the Form-A-Drain webpage at https://www.formadrainsolutions.com/product/platon says: “Spray-on and peel & stick methods can drive hundreds of gallons of water from concrete as it’s curing to the inside of your basement where you don’t want it—this curing/evaporation process can last up to 3 years.”
While I think I understand and can explain to the builder the advantages of waterproofing, what do I tell him about why those advantages outweigh the “driving water inside” argument?
Thanks in advance!
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