Burying Brick
It's a bad idea to cover brick cladding with regular soil. Start by separating the brick from the moisture in the soil using a drainage mat.
I would like to add some retaining walls on the sides of my house, but my landscaping contractor says it is not a good idea to bury the existing brick cladding below the ground. If that’s true, what are my options?
—Dianna Hughe, Omaha, Neb.
Steven Fechino, engineering and construction manager at Mortar Net Solutions, replies: Your landscaping contractor is correct. It is a bad idea to cover brick cladding with regular soil. Brick is porous and will absorb moisture from the soil, which could ultimately find its way into your basement or crawlspace through capillary action (wicking). But that doesn’t mean you have to scrap your landscaping plan. To minimize water infiltration, I recommend the following steps.
First, separate the brick from the moisture in the soil by installing a drainage mat directly against the brick. Use a mat that is suitable for below-grade applications. Keene Building Products TriDent Dimple Drain 025 is one product. If you choose to use a self-adhering membrane, keep in mind that if you or the next owner of your house ever wants to get rid of the retaining walls, removing the membrane will likely damage the face of the brick. Next, backfill up against the drainage mat with washed 3/4-in. (#57) stone, also known as dense graded aggregate (DGA). You only need about 12 in. of #57 stone between the wall and the regular soil. Finally, install a landscaping fabric between the rock and the soil to prevent the soil from working its way into the rock and reducing its permeability.
Photo courtesy of Greensward Design Build.
From Fine Homebuilding #322
RELATED STORIES
