You're right Annie they are an unballasted boat of monocoque ply construction around a heavily built center board. Capt. Short recommended plastic jugs filled with water packed around the cb if additional ballast was required.Interestingly, I read of an "Emperor" pelican built by doubling the 12 ft. Plans, 24'x 12'beam with 4' freeboard. Pretty good bang for the buck. BTW, I am enjoying following your build. That's a nice well thought out design.(Check out -CL Victoria b.c. " junk rigged ketch" . 26ft Kenner Privateer that's a real beauty. )