I now have a pair of 20' Fir 2x4s sitting in my garage waiting for me to get to work on building an SoF following Chris Cunningham's book. Upon seeing them strapped to the roof of my car and learning their purpose, my twelve year old daughter asked if I would build her one her a kayak too. Relishing the thought of getting on the water with her, I said yes (I actually told her I would "help her build it"). Now this begs the question of the dimensions of the kayak. She is about 5' tall and on the slim side, so my thought was to shorten the kayak from 18' to about 14 and making it a little wider than the four fingers rule to give her a little additional stability.

Will she outgrow the kayak? sure enough, but at that point I will wipe it down and hang it up on the wall in the house and build her another one or let her use the 18' boat I'll be building for myself at the same time.

So my question is the following - can I figure out the spacing of deck beams and the like for the 18' and then reduce proportionally on a 14/18 basis, or should I just build two 18' boats and let her grow into them. I would like to get the basic measurements down on paper (in addition to the story pole) before I cut anything to length and get to work.

Thanks,
Gero