GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Waterproofing and precast concrete walls

ColbyForester | Posted in General Questions on

Hello, I am thinking of using Precast Concrete walls for my basement. The warranty and claim that there system is waterproof and requires no waterproofing other than a french drain at the bottom below the wall. Do I still need to go over the top of that with dimple drainage mat over the walls or is the concrete sufficient enough? Obviously, I would like to do the most cost effective method but do not want to skimp on waterproofing either.

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. GBA Editor
    Brian Pontolilo | | #1

    Hi Colby,

    Beyond code minimums and the requirements/installation details of the product you are using (what product is it, by the way?) the level of waterproofing you should do on basement walls has to do with site conditions, your own comfort level, what you want to do with the basement, etc.

    For example, is it a wet site at the bottom of a hill? Do you plan to finish the basement? If you are answering yes to questions like these, I'd consider going well beyond the basics, like maybe including a dimple mat. Is the site dry and you will only use the basement for running mechanicals and some appropriate storage? Well, there's a lot less risk and maybe you don't need to do much more than the basics.

    Anyway, were are two articles that may be helpful: Using a Dimple Mat to Keep a Basement Dry and All About Basements.

  2. harrison55 | | #2

    Here in Central Virginia builders routinely land the precast walls from Superior in clay soil with no treatment. They say no problems! On my own install, we sealed the precast concrete walls with liquid concrete sealer, just to be extra safe. One year on, no problems at all.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |