Kendall, I presume you goal is "positive foam floatation". The floatation foam should be installed primarily above the DWL and as far outboard as possible or the tendency is for the boat to 'turn turtle'. This is one of the major reasons why so few boats carry positive floatation - it is a tough design parameter to achieve and even tougher to sucessfully execute in practice. If you install that much foam in a M-15 the boat will promptly turn upside down and need to be pumped dry before it could be righted when the boat took on large amounts of water. The better solution is to practice prudent seamanship and excellent maintenance such that water entering the boat in large volume is minimized and when or if it does, it may be effectively removed in an orderly manner. Good luck if you foam your boat - it is a messy job at best. If polled, I think the list would say it would deter from the boats resale value. Check out 26.73 cubic feet to see how much room your boat will be left with for interior space. MO FWIW your actual mileage may vary. Good Luck, Gary O M-17 #316a **************Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duf... 2050827?NCID=aolcmp00300000002598)