I think that the question is- why is this necessary? Is there a reason you need a kayak with the weight that using foam instead of cedar might possibly under some circumstance provide?

Don't assume that people building wooden boats are a bunch of old curmudgeons who like to putz with wood and yell at kids to get off their lawn. There are a lot of people who are building performance kayaks, and some at very light weights, because they want the performance benefits of this type of composite construction- something which isn't really available in the manufacturer marketplace. Wood is used because for a very long time it has been the best choice. If foam were the better (or even more viable) option it wouldn't be hidden in some dusty corner of the internet; everyone would know about it.

So- just to make sure that I don't seem too negative- there are plenty of things that have been done just to say you've done them. Goodness knows I've done a lot of them. But, sad to say, I am old enough to have learned that unless you're chasing an anecdote that was codified through something akin to the telephone game, there is probably a good reason why things are done the way that they're done. A lot of headaches can be solved by trying to figure out why they're done a certain way before deciding to do it differently. If nothing else- you will go through the thought process and reason out what might be the best solution.

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