I had a couple basement contractors out to look at putting in an egress window. One of them said he expected it to be harder than normal on my house, because builders in my area in the 50s didn't use an external form on the first pour of the basement wall so that the foundation wall is probably kind of bell shaped on the outside making it really thick near the bottom. The other contractor didn't mention anything about it.

It wouldn't shock me; they cut every other possible corner. But I can't find anything online about builders doing this. The ground is frozen right now so I can't dig down and find out for sure, but this could make a substantial difference in the feasibility of the project.

Has anyone else heard of this?

2 Answers 2


It seems unlikely. Concrete is expensive, and has always been.

Formwork is reusable, and you don't waste twice as much concrete pouring the foundation if you use formwork. In most areas, the dirt will not stay put well enough to pour a wall directly against dirt.

It's possible, but does not seem terribly likely. Then again, most egress windows are not all that low in the wall, so if it was "the first pour" (footing, which is below floor level) it should have no interaction with your window - at which point I'd be thinking "hmm, is this contractor setting me up for an upcharge?"

  • concrete wasn't as expensive as you think in the 50s
    – DMoore
    Jan 27, 2021 at 5:25
  • And removing the cost of labor and material for formwork can reduce the time for the job - more jobs more profit even if and not sure of your if that concrete was expensive...
    – Solar Mike
    Jan 27, 2021 at 6:08
  • I have seen single form in Ohio and thought how the heck did they do that. But agree with ecnerwal the bell was well below the level of an egress window.
    – Ed Beal
    Jan 27, 2021 at 15:34

Installing, removing, and cleaning formwork for re-use takes labour, that's expensive. if the earth is stable enough to form half, or all of, the below-ground formwork that's a win for the builder.

If the foundation needs to be waterproof (like for a finished basement) then waterproofing the outside surface usually works best, also the drains and other stuff that need to be installed on the outside and the smooth surface typically desired on the inside start to make a full formwork look more attractive.

  • My garage foundation was poured in the 90s and they didn't bother with form work. They just dug the trench, had it inspected, (put pea gravel in the bottom IIRC), and poured concrete. I didn't have the knowledge at the time to even begin to question it.
    – FreeMan
    Jan 27, 2021 at 14:15

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