Keel Made of Bridge Timber

[stormkreau]

I have a 43-foot schooner where the keel is one complete timber of pressure teated fir from the 1940's. It seems to be wonderful so far, especially WRT rot resistance. I've had lots of rot problems in the planking and some in the frames (oak and fir), but no problems at all with the keel and surrounding wood.

Was wondering, though, what you guys think about that as the books and such that I read say to use oak or other rot-resistant hard-wood.

What are the structural risks or problems that I might run into with pressure treated wood keel?