Pound for pound you are going to have trouble finding a foam that is stronger than wood. While you may be able to make a lighter boat using the same thickness strips in foam, it will probably be weaker and if you succeed in making it as strong it will be heavier. Using exotic fabrics can make a lighter/stronger boat, but it is really hard to beat wood as the core. There may be good reasons to use foam, but if strength and weight are an issue, don't discount wood.

: I saw a "Laughing Loon Georgian Bay model" on the water recently
: and it is a very cool kayak for sure. I am familiar with the strip-built
: process(never built one though). Since I am a composites professional, I
: was wondering if anyone has any thoughts on exchanging the wooden strips
: for foam strips? There all all sorts of marine grade foams that may lend
: themselves to this technique. Using foam and graphite could yield a
: lightweight yak. I was concidering the use of Rohacell foam, or perhaps
: PVC and epoxy, or vinyl ester marine grade (hytex) resin. No particular
: design identified as of yet.Input welcomed!

: BTW-There are a few on-the-water shots of the Loon posted on site/pages
: linked below, which were taken during a recent kayak fishing derby in
: Redondo Beach, California at King Harbor-FYI . Thanks.