Waterproof Expanding Foam

Discodog

I have a difficult problem. I need to make a void waterproof at the back of an existing pond. To make matters worse the access is almost impossible as it's under a stone shelf (waterfall).

I have read that expanding foam can be painted. Could I paint a sealer on it to make it waterproof enough to hold water when it's submerged ?

gctest50

you can get "winter" foam - want to be sure the foam / paint won't kill your fish though

http://www.uksealants.co.uk/illbruck-fm617-high-yield-expanding-foam-%28hand-held%29--p220.html

whupdedo

Make sure to wet the hole before putting in the expanding foam, wait for it to cure, cut back and then what I would do is id get some tech7 and fully coat the cut side of the foam with tech 7 using a small trowel or paint scraper

Discodog

gctest50 wrote: »

you can get "winter" foam - want to be sure the foam / paint won't kill your fish though

http://www.uksealants.co.uk/illbruck-fm617-high-yield-expanding-foam-%28hand-held%29--p220.html

No fish fortunately.

Discodog

whupdedo wrote: »

Make sure to wet the hole before putting in the expanding foam, wait for it to cure, cut back and then what I would do is id get some tech7 and fully coat the cut side of the foam with tech 7 using a small trowel or paint scraper

I used some tech 7 to "glue" some small pieces of stone on a waterfall & it failed to adhere. My concern is if any solvent in the tech 7 or sealer might react with the foam.

fergal.b

If you want to seal it you can coat it in epoxy resin or to make it stronger coat it in fiberglass cloth and then resin, this is what we do on boats to seal in foam buoyancy blocks.



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