CMU garden wall not waterproofed, without drainage… now what?
dsmcn
| Posted in GBA Pro Help on
East TN: Climate Zone 4A, annual rainfall about 50″.
CMU block retaining wall was built without drainage or waterproofing (beginning to look like the builder skimped on the footing also—but that’s a different issue). Wall was coated with Thoroseal it seems, and has been painted twice. Paint is failing, and there is mold and even moss on the face of the wall.
What to do? I added a curtain wall drainage in front of it to protect the crawlspace, but we are still looking at a messy wall through our living room sliders. What materials and method can I use to provide a new face on the wall?
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Replies
If you aren't worried about the retained soils sliding into your house, you could pressure wash the paint off and do nothing. When the wall starts to fall or your budget allows, you could rebuild the wall using an acceptable retaining strategy.
Unfortunately, because of its proximity to the living room, it needs to be a feature, not just a clean concrete wall with a exposed cracks that make it look like a job cheaply done. One thought was to apply 1x treated furring, and attach tile backer board, then either tile or simply plaster over it. I would leave 6" at the bottom, and cover that space with a false base of patio pavers run vertically.
Also considered Hardi 4x10 sheets applied the same way, or even EIFS. The issue with these solutions is how to finish the top of the wall. There is an upslope grade above it, covered with ivy.
David,
Besides the aesthetic function, does the wall meet a geotechnical need? If its failure would cause a problem, I don't think you want to "paper" over it. How was the wall spec'd in your drawings, and are you still covered by your builder's warranty?
David,
A CMU retaining wall with soil behind it and no drainage is eventually going to fail.
You can put any type of lipstick on this pig that you prefer, but eventually you're going to have to rebuild the wall.
-- Martin Holladay