Water proof membrane over below grade concrete

February 1, 2007

We are building a house in a low lying area which is sitting on 22 feet of sand before it hits the clay. I intend to slope the ground away from the foundation and I am wondering if it is necessary to put in weeping tile. We have a 4 foot crawl space.

Walter, Langley

A. Yes, please plan on drain tiles as well as applying a water proof membrane over all below grade concrete foundation walls. Drains may be drained to the down slope at the rear of the lot. If you live in greater Vancouver we have this service available through the Shell Busey HouseSmart Referral Network that specializes in drainage. Call 604 542 2236 and ask for our drainage specialist to contact you.

Also, please consider insulating the concrete walls in the crawlspace with 1 1/2 inch rigid foam insulation, application using foam adhesive.

Thanks,
Shell Busey