3 Comments

1. 
   Mark | Feb 04, 2010 07:50am | #1

   Where would the Drain Tile drain to
   I have a 1958 Ranch style home in southeaster South Dakota. It has a concrete block uninsulated basement that has a continuous, uniform clay soil grade about 5-6 feet deep. No water issures, a few areas of cracks in the mortor. A sump inside the basement, with no interior or exterior drain tile, always has two inches of water in the bottom when conditions are dry. I am thinking of excavating arround the exterior to install waterproofing, drain tile, rock and filter fabric as noted above, and enough EPS rigid foam for R20 (do I need more???). With no option for draining to daylight, where would you run the Drain Tile to--a drywell 15 or more feet away from the house or into the interior of the basement to the sump? Thanks

   Mark Dahlhoff Vermillion, SD

2. GBA Editor
   Martin Holladay | Feb 04, 2010 09:18am | #2

   "Draining to daylight"
   Mark,
   In hilly Vermont, it's usually easy to "drain to daylight." In the flatter sections of South Dakota, a drain to daylight may require running your 4" or 6" pipe all the way to Missouri — not a good solution.

   It makes little sense to connect exterior drain tile to an interior sump until you have a good plan for draining the sump. A sump is usually drained with a sump pump, either over the surface of the ground to a suitable distance away from the house, or to a town sewer (where such a connection is permitted).

   The other option is a distant dry well, as you propose. The farther away from your house, the better.

3. 
   jbmoyer | Feb 06, 2010 03:21pm | #3

   Flat Lot, Dry Climate
   Is there a section in the IRC that covers perimeter foundation drains in dry climates? We get about 16 inches of precipitation in our area, and it's not very common to see a perimeter drain around the foundation unless the site has a high water table.
   Daniel referenced the IRC stating "Concrete & CMU foundations that contain habitable or usable space need drains [405.1], unless there is good natural drainage [405.1X]" Does this mean ALL foundations with out good natural drainage? And what is "good" natural drainage by the way? Im assuming good slope, and somewhat permeable soils. And what about flat lots in dry climates? Sloped lots in dry climates?
   I know that good sized roof overhangs can deflect the moisture away from the foundation wall. I also know to grade away from the building, but this may not be sufficient drainage in the eyes of some building inspectors...