I am installing an exterior foundation drain around my 10 year old brick house. I have a poured concrete footing, with brick veneer down to the footing. How should I moisture proof the below grade brick?
Engineered-stone shower panels are waterproof, but proper installation relies on tight seams and silicone sealing.
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One of the best moisture proofing systems is sticky rubber membrane. I don't know the brand, but it's like Grace Ice and Water Shield that's used on roofs, but it's formulated for burial. It's thick, impervious, and bridges cracks exceptionally well. It's about the best system you can install.
You may have another problem to take care of. It's not standard construction technique to have a veneer wall go to the footing. There is supposed to be a 1" air space behind the veneer, and at the base of the wall, weep holes for the water that gets behind the veneer to drain. If the base of the wall is below the ground, obviously, you can't have weep holes. Maybe this is taken care of by some technique that you just did not describe in your post.
Normally, the 1" gap between brick vaneer and block is filled up to the level of the weep holes, but really, I don't know if the whole house is brick vaneer, or just the foundation. If the house walls are not brick vaneer, there is probably not any weep holes. If it is a brick vaneer house, normally the weep holes go around the foundation at the level of the bottom of the floor system. The below grade block that creates the brick ledge is just to save money, and the brick ledge is usually stepped to accomidate slope in the lot. So, the way your foundation is constructed is more than likely fine.
You didn't say if it is a basement or crawlspace. Normally they are handeled differently. Once you apply the coating or membrane, plan on installing some kind of below grade drain board over the damp-proofing. This helps water to run down the face of the foundation wall and into the drain tile. It also helps to prevent rocks, etc that are in the backfill from damageing the foundation coating. I'm guessing you already have a water problem, so consider using schedule 30 PVC pipe, or something else better than black corogated pipe for your drain tales, and make them drain to daylight. A drywell is just a big pot that is gonna fill up on the day that you least want it to.
Thanks - to answer your questions: My 2 story house is all brick vaneer with a crawl space. I have one row of 12" block on the footer, then the brick vaneer on the outside and 8" block foundation wall up to my floor joists (about 3' high). I don't see any weep holes at all in my brick.
With it constructed that way, you might not be stopping all water from getting into the crawl space even with a perfectly sealed exterior below grade. Any water that penetrates the brick veneer will migrate down to the balock and find it's way to the interior.
What I would do for the exterior though is to parge coat the bel;ow grade brick to fill the moratr joints and create a smoother surface, Then paint on a slurry of Thoroseal. Then any asphaltic foundation coating..
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