Construction Tips

Ideally, you should mark layout lines with a crayon or chalk line, especially on a complex foundation with varying grade. On a simple foundation, it might be safe to just instruct the waterproofer to keep his work so many inches from the top of the foundation. I like to see waterproofing as close to finish grade as possible, but no lower than 6 inches in any case. Don't leave form-tie holes that are below grade unprotected. Work out ahead of time what you're going to do at basement windows and bulkheads, porch foundations, and intersecting walls that don't have to be waterproofed.

When deciding what walls get waterproofed, follow this basic rule: Waterproof any foundation wall that has earth on one side and usable space on the other, including crawl spaces. Extend waterproofing at least 12 inches onto intersecting walls that don't have to be waterproofed. You might want to continue the waterproofing on other walls if it's a very wet site. Under extreme conditions, water has been known to travel through the keyway along the footing and into occupied space. Consult with the architect if you have any doubts.

Check the waterproofing manufacturers literature for temperature limitations. You're probably okay applying waterproofing on a cold day if you're working with a solvent-based material. But watch out if your material is water-based. The lower limit for some products is 40F.

Return to Waterproofing Concrete Foundations

Site Sponsors