Re: [GBlist] Foundation Drain placement

[Sacie H Lambertson <dlambert@grasshoppernet.com>]

Hello Eli, Jim et al,
	When I put a foundation in this last time--bermed into a hill with only
one part of the south end walk-out (where I did a dif. foundation detail),
I considered the various places one could put the perf. PVC.  I knew that
the easiest/least expensive footing would be a trench footing, however, it
makes sense to me to place the top of the drain no higher than the top of
the footing, so I had the concrete guys form the footings.  My thinking
went this way: the place most likely to leak would be at the joint between
the wall and the footing, therefore a drain slightly lower should handle
any migrating water (I also placed a small network of interior drains under
the slab, this connected to the outside drain which, on this site, was
brought to light).  It doesn't make a lot of sense to me to place the drain
right where a leak would be most likely to happen, ie on top of the footing
right next to the joint.  And yes, if one has a fool proof way to seal this
area, then do that too, but I would still place the drain lower.
	And I agree with Jim that the concrete guys wouldn't do it right, so we
did it ourselves,  got the right slope and placed good clean gravel over
and around the perforated pvc (with the holes not on the bottom but on the
down side).
	If one weren't willing to do all that work themselves, I would suggest
that the concrete subs use a product called 'Form a Foot'---I think that's
the name.  Basically it's a form for a footer with a built-in drain
alongside.   Lumber yards carry the forms but you'll probably have to call
around.
	We  placed a sealant on the outside of the wall as well, but I think Xypex
mixed with the concrete would have been a better and less expensive
waterproofing solution.  There are other drainboard-like products out there
as well btw.
	I don't see any point in placing a perf. drain below the footing.   I am
sure that water takes the easiest way out.
						Sacie Lambertson


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