3&1/2 sq ft of 3" thick foam if you're doing a bulkhead and small saddle
5 sq ft if you're doing a bulkhead and full length saddle.
If you're going for just kneecups instead of a full bulkhead you can take about 2sqft off either of those; I'd recomend making a full length saddle that's shaped to hold your knees and thighs out if you're not using a bulkhead.
Joshua Kelly - "More George Smiley than James Bond"
CBoats Moderator - Not necessarily representing the CBoats staff though...(I'll use words like "moderator", "We" and "CBoats" to make it clear when I am)