On Jan 24, 10:32*am, Joe wrote:
My sump pump stick about 3 inches over my sump pit. I would like to
cover it with some heavy material so it muffles the sound and provides
somewhat of a seal. The only thing I can think of is to cut up a piece
of tarp and glue some of that egg shell foam sound proofing material
on top. It doesn't need to be pretty. Any other ideas that might be
more effective?


I would use 2 inch rigid fiberglass panels 6lb/cu ft (Manville) to
construct a 5 sided box, then put that whole box over the top. The
Manville heavy fiberglass panels stop sound dead in its tracks, I've
used it to construct sound studios, isolation booths, and micing boxes
for guitar amps etc. Its easy to cut out the pipe holes and ou can
use duct tape to make the sides hingeable for removal, fireproof. Its
this stuff, available at a professional lumber yard that supplies to
commercial builders.

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