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Community and Q&A

When is a sump pump necessary?

Emel | Posted in General Questions on

We had hoped to avoid a sump pump in our finished crawl space to avoid possibilities of mold or mildew in the home (pretty serious allergy with a family member). We have a sloped site that would accommodate a drain to daylight. However, we’re being told that in our region, even if you can drain to daylight you should have a sump pump installed as a backup as drain to daylight can get plugged by animals and sometimes freeze shut in the winter. We live in a fairly wet area and I know our neighbors with full basements have sump pumps that run constantly (also why we’re only doing a finished/ventilated crawl space, building up as much as we can, and bringing in dirt around). They do not have drain to daylight.

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Replies

  1. Deleted | | #1

    Deleted

  2. Malcolm_Taylor | | #2

    Emil,

    If you think a sump pump is necessary you can install it outside too - although as Chris said, they are all well sealed now.

  3. walta100 | | #3

    The way I see it installing the pit and having a plan for the pipe costs almost nothing so why not.

    Generally footing drains are installed poorly and often to high. If you came make them install the drain with slope and rock inside of filter fabric 10 inches below the slab it is very unlikely that you will need a pump assuming the walls get coated in modern waterproofing.

    Walta

  4. mgensler | | #4

    We live in the north and don't have a sump pump nor do any of the homes built in our neighborhood around 1960. However, the new build infill all seem to have sump pumps. My guess is it's the cheaper solution vs doing the grading and making sure the pipe doesn't get crushed during backfill. Personally, I wouldn't want one as it's another point of failure. With the almost annual 100 year rain events we have now, I'd trust a gravity drain 4" sdr to move much more water than a 2" pipe on a sump pump. Maybe a compromise is to have them install the pit as gravity drain and you can add the pump later if you decide.

  5. Tim_O | | #5

    We are in Michigan, we were lucky enough to be able to have a drain to daylight. We have exterior and interior drain tile that ties into the daylight drain and a sump pit. We also do not have traditional footings, since we have superior walls, so water can move freely in the footing, sort of negating the need for interior/exterior drain tile.

    All that said, I do intend to install a sump pump. I will seal it in place, so it is radon tight as well. Our current house has a radon system, basically sealed sump pit with 1/4" plexiglass. There should be no mold from the sump pit/pump/drain run entering the house with this type of setup.

    My parents have a sump pump that got clogged by an animal. So I guess it can happen to both... Redundancy is always best, especially for a finished basement.

  6. gusfhb | | #6

    I dunno, sump pumps always seem an afterthought. Foundation sealing, exterior foundation drains, proper roof drainage all should eliminate the need. I guess if your water table is that high.

  7. jberks | | #7

    I like to use plumbing effluent pump and basin for the ground water system. It's sealed, and has a ventilation port which I use for radon mitigation. I tie it to the plumbing vent system.

    Even if I had a slope to daylight for groundwater, I'd probably install a sump anyway as redundancy. They're good to have. And the good ones like liberty pumps are pretty rock solid.

    Last thing I'd want is water damage in the house because the daylight outlet pipe was blocked and didn't notice it.

    Jamie

  8. Sinaritt | | #8

    Even with good gutters and grading, I still have a steady trickle of water running through my perimeter drain to daylight throughout the year. I'm on a hill, and water drains underground across my property. A daylight drain it great, unless it's connected to interior drain tile and you happen to have elevated radon. Then it will complicate a sub-slab depressurization system. I'm in NY and the 4" daylight drain hasn't frozen over yet. I also installed an interior sump pit with a sealed cover as a backup. I don't think a sealed sump pit would significantly contribute to mold or mildew in the air.

  9. Expert Member
    DCcontrarian | | #9

    Being in the north has absolutely nothing to do with whether you need a sump pump.

    I would try to do everything possible to ensure you don't need it. But if you need it, you need it.

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