Sometimes it can be hard to judge how much putty you need for projects. A 1 Lbs can of Durham’s will make about 1-1/2 cups of putty (or 21 cubic inches) when water is added. 3 Lbs of product will make 63 cubic inches. 82 Lbs would make 1 cubic foot. To put that into perspective, 100 lbs of water putty covers 60 square feet at ¼” thick.