Boat Marine

How light is lightweight, marine grade concrete for boat building?

I am considering to cast myself a planing boat out of marine grade concrete - I know they use it for sailboats with displacement hulls, but would it work for a light boat, too?

What you might try doing is to cast into the concrete fillers that will make it lighter, so that it will have less weight to displace. I know that hollow glass spheres have been used (very tiny, a by-product of smelting fly-ash, oslt.)

I think you can also whip air into concrete while it is curing, then coat the finished product with a skin coat of concrete-epoxy mix or paint. If you cast in sealed air bladders (glass bottles, fused shut...? At least that way you are using recyclables) it may improve the floatation characteristics.

---