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Community and Q&A

Sump pump or no sump pump?

user-2895420 | Posted in General Questions on

We are just breaking ground on our “final” home in Asheville, NC. We had spec’d out a sump pump in our bid, but our builder is saying he almost never installs them and doesn’t feel we need one. We’ve had sump pumps in all of our 7 previous house basements – so we’re a bit nervous about not having a sump pump. Some of those previous sump pumps would run every time there was a hard rain, some almost never ran (primarily when the house had an exposed basement).

Our home is on a 30% slope and will have a full walkout basement with one side completely exposed, and both side basement walls at least half exposed. We are paying special attention to concrete foundation waterproofing, appropriate backfilling and proper installation of an external perimeter drain tile that will “run to daylight” and drain downhill from the house. There will be a swale uphill from our home, directing water away from the house site.

There have been over 15 inches of rain here in the last 3 weeks, and surprisingly, all the soil around and in the foundation is remarkably dry. The foundation soil was a 1’ + layer of topsoil, and everything under that is primarily clay, with lesser amounts of mica and what appears to be sandstone. The clay here in Asheville is nowhere near as dense or “sticky” as what we’ve experienced in our previous homes in the Midwest.

So our question is… is a sump pump necessary? We may never need it, but at the same time, we’d hate to have to go back and install one if basement water ever became a problem.

Thanks in advance for your thoughts/input!

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  1. GBA Editor
    Martin Holladay | | #1

    If your new house has exterior footing drains that run to daylight, the answer is, no, you don't need a sump pump. You don't even need a sump.

  2. user-2895420 | | #2

    Excellent... and one less potential radon issue to address. Thanks for the quick response!

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