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Not That Kinda French drain...

Not That Kinda French drain...

Not That Kinda French drain...

In ~1950, my family moved into a new house, which turned out to have a wet basement.
The builder went bankrupt.
At his expense, Dad had the interior basement perimeter excavated to a depth of 1.5' and a width of 1', then filled with gravel, terra cotta pipe, tarpaper, and more gravel to a level flush with the bottom of the slab. The contractor then placed 1x4 wood next to the concrete block wall, and poured concrete level with the floor. Then the 1x4s were removed, leaving a perimeter gap. ... and of course a pit big enough for three pumps was installed.
That's still working today.

Fast forward to now; I'm buying a new house.
... which after recent heavy rains developed a leak at the floor/wall intersection, sufficient to flood a small area of the interior floor and wet the thick fiberglass insulation hung on the interior of the basement walls.

The builder's remedy was to drill two 1.5" dia holes through the floor adjacent the pilaster where the leakage occurred.

I was suspicious that the pilaster hid a crack, since nothing bears on top of it. The builder says the pilaster is just there to reinforce the long straight wall of which it seems to be a part, and not to repair a crack, which he assures me is not there.

Couple days later, I visit, and the floor is dry.
The insulation is still wet; builder says he will dry it in place.

He has also (finally) installed the sump pump in the pit which has been there for months.

Coupla days go by, and I am inspecting the outside of the house for a different reason, and notice that the sump pump is cycling about every ten minutes, discharging maybe five to ten gallons at a time. It hasn't rained much recently, the soil has been rough graded away from the house, and the only water on the future lawn is what has been coming out of the sump pump, which has produced minor erosion.

The builder is a real nice guy, and has a decent reputation and considerable experience.
... but he's not real big on writing things down.
On the phone he's offered his personal guarantee that I will have a dry basement for the foreseeable future.

The extent of his remediation so far comprises the two drilled holes, which I have probed and found gravel, so there's at least part of a French drain there.

I described my Dad's adventure in some detail, and noted specifically that Dad's contractor provided a perimeter slot through which water could drain from the top of the floor down into the French drain, whereas the extant house, likely to be mine in a few days, lacks any such perimeter slot or other floor drain mechanism, save the two added holes.

He replied "It's not that kinda French drain".
... and he seems intent on leaving it as is.

So... Is there "another kinda" French drain that magically passes water through the floor/wall joint without a visible gap?

Would I be crazier than usual to just accept it as is, and plan on drilling a few more holes into the French drain whenever more water shows up?

Mike Halloran
Stratford, CT, USA

RE: Not That Kinda French drain...

Your Dad's fix was the "cheap" way. A better fix would be what you apparently have. The only question I have deals with the porous back-fill around your exterior drain pipe. That needs to filter fine soil from coming along with water. Chances are it is done properly. If you see any soil coming along with the pumped water, there might be a problem, but likely not. Unfortunately many building codes dfon't recognize that these drains can plug up if soil comes along with the water. By the way, eliminate the word "French Drain" from your description, since they definitely were not filtered back when that term first came to be used.

RE: Not That Kinda French drain...


Er, what exterior drain pipe?

The corrugated poly pipe carrying pump effluent seemed to be running clear, so I'm guessing that there's filter fabric where it should be.

Mike Halloran
Stratford, CT, USA

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