Interior Foundation Drain (Damp Proofing)

Foundations, Floors, and Walls Are Critical Green Connections

Air sealing is imperative. The connection between concrete foundations and wood framing is a place prone to air leaks and moisture problems. Wood is often warped, and concrete is rarely flat. There are at least three places for air to leak in and probably a lot more. Leaky connections can mean energy, moisture, comfort, and IAQIndoor air quality. Healthfulness of an interior environment; IAQ is affected by such factors as moisture and mold, emissions of volatile organic compounds from paints and finishes, formaldehyde emissions from cabinets, and ventilation effectiveness. problems. Extending the wall sheathingMaterial, usually plywood or oriented strand board (OSB), but sometimes wooden boards, installed on the exterior of wall studs, rafters, or roof trusses; siding or roofing installed on the sheathing—sometimes over strapping to create a rainscreen. past these connections is a good first step whenever practical. Caulks, adhesives, spray foam, and gaskets can seal them up tightly.

Keep water at bay

Unless you live in the desert, the ground is always wet; and that ground water is always pushing its way in. Footing drains can carry away bulk groundwater, but foundations also have to disrupt capillarity. Water in the soil will wick all the way up to the roof framing if you let it. CapillaryForces that lift water or pull it through porous materials, such as concrete. The tendency of a material to wick water due to the surface tension of the water molecules. breaks such as brush-on damp-proofing, sill sealer, and rigid insulation block this process. A foundation is a bad place to cut corners because problems are expensive and complicated to fix after a house is finished.


Download: PDF | DWG

Tags: , , , , , , , , , ,
Feb 23, 2012 7:03 AM ET

Edited Feb 23, 2012 7:04 AM ET.

Response to William Wingett
by Martin Holladay

Here is an article to get you started: Building an Unvented Crawl Space.

Feb 22, 2012 6:56 PM ET

Crawlspace -insulating and air sealing
by Peter Yost

Best way to deal with a crawlspace is to treat like a "short" basement: insulate and air seal at the perimeter walls and making sure that you have a vapor barrier down on the crawlspace floor to stop moisture from moving into this now "interior" space.

Check out the crawlspace details on GBA.

Feb 19, 2012 1:02 PM ET

Old House Crawl Space
by William Wingett

My Sister has an old house that sit appox. 4 ft off the ground. It has no insulation in the floors and they won't put any in because they were told that they would had mold problem. What are your suggestions to fix the moisture problem and the insulation problem.