Yes, I believe this is a perimeter drain. We also have a sump pump, but I've never seen any water in it. We are in a mixed climate (central NJ). The basement walls only extend about 18" above grade. I have another question. What about insulating only half of the wall? My foundation was constructed with poured concrete half way up, then the top half is cement blocks. The framed wall is about an inch away from the foundation at the bottom, but 1/2 way up, the wall is closer to 4" away from the blocks. I could easily put insulation on the top half of the wall without worrying about it touching the foundation. Would this be worth while? Also, I was thinking about using Drylock to perhaps help with the humidity. Without removing the wall framing this is going to be a real hassle, so I don't know if it is worth while. Would I do only the concrete block part of the wall, or is this supposed to be applied to the solid concrete lower half of the wall also? Thanks guys for your replies.

To keep water out of your house the primary barrier is the brick and the secondary barrier is building paper or housewrap over the sheathing. Making a good repair is difficult if either of these barriers is poorly constructed or missing without tearing a lot of the wall apart. A wall system is designed to accommodate the interior and exterior climate conditions because that is what determines the movement of water vapor through the wall. In general, in a warm climate with air conditioning a vapor retarder belongs on the outside, and in a cold climate it belongs on the inside.

Be sure you understand the options. There are 2 kinds of crawlspaces allowed by the IRC: Vented and Unvented (aka "sealed"). The terms "unvented" and "sealed" are misleading because this type of crawlspace is not completely sealed or unventilated. The IRC code requires that both of these types of crawlspaces be "ventilated" so that moisture does not collect and encourage the growth of fungus (whether from the ground, condensation on the slab, etc.) by one of the following methods: 1) "Vented" Crawlspace - install vent openings in the exterior wall of the crawlspace 2) "Unvented" Crawlspace - inside the house supply to or exhaust from the crawlspace a small amount of air with a return air path to or from the house and insulate the exterior walls of the crawlspace. Both crawlspaces must have a vapor retarder at ground level and an access opening. For more information see IRC section R408.1, 2, & 3.

I am renovating the basement of my townhouse. The .walls are concrete block. Three walls are ground-side and the other wall is common to the adjoining townhouse. I am replacing the paneling with drywall. There is no insulation. The space, however, is a consistent comfortable temperature. There are vents for HVAC. The ground-side concrete block walls have been painted with DryLok. The gap between the framing and the concrete block wall is 5 3/4 inches. Fiberglass bats will be installed in the framing. Do I need a vapor barrier also, and, if so, which type? As an FYI, there has never been a water issue. Thank you.