DryLok foundation sealant. You can buy it in the paint section or concrete section at Lowes or Home Depot. Its white, got some grit in it, but dries SUPER fast. It's extremely waterproof and durable. 2 gallons ($50) put 3 coats on the entire interior of my 8'x 4'x 3'enclosure. Make sure you get the water based
http://www.lowes.com/ProductDisplay?partNumber=41348-96-27513&langId=-1&storeId=10151&productId=3033249&catalogId=10051&cmRelshp=req&rel=nofollow&cId=PDIO1


