12-11-2017, 02:57 PM
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#10 (permalink)
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Thalmaturge
Join Date: Mar 2011
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Or maybe just add a bag of this to 1cuft of portland cement?
https://www.amleo.com/horticultural-...iABEgImK_D_BwE
First porosity material that popped into my head, and it looks like it's a thing:
SCHUNDLER COMPANY--Perlite Insulating Concrete |
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