How you prevent water from coming into a slab on grade at the bottom of a wall?


How would I detail the connection between the wall and floating slab?

Brendon Fraser July 17, 2020Last updated: Sept. 25, 2020

Hello all,

I am an architectural designer who, personally, love slab on grades. However, one big worry I often have is water damage at the base of the wall. Due to the wall being so close to grade, I worry about water pooling inside the sill of the wall. What is the proper way to design a slab on grade to prevent water damage and a failure of the house?

If you can, a simple sketch would me leagues beyond helpful.

Responses (2)

Brendon Fraser July 21, 2020, 12:36 a.m.

It's mostly a worry up here (Haliburton Highlands Area) due to snow buildup around the base of a house. Normally, four our houses here, we design them with 8" of concrete basements above grade, and I know that my boss was worried about the slab itself only raising up maybe 3-4" above grade. As the snow melts and builds up against the wall, there is potential for snow to enter the envelope much easier.