Re: what wood for stringers???
Cedar, cypress and redwood are all oily woods that resist water damage well. Cypress is one of the top choices in my neck of the woods. It grows in swamps (which we have plenty of) and is virtually impervious to water damage. Cedar is also a good choice. Oily. Redwood is expensive, but the other two ain't cheap either . As a journeyman carpenter, I don't think I'd put KD doug fir in a boat. It's not much harder than balsa wood. Sure, it's light, but once kiln dried, it soaks water like a sponge. Ever been in an attic to repair a leaking roof and seen or felt what a rotten doug fir timber looks-feels like? Or torn out a leaking tub or toilet that had fir framing behind it? It's fine for framing walls in a house that will never see a drop of water, but it's not necessarily strong-horizontal sheer strength. KD doug fir is used extensively in the trades where a lightweight structure is needed. It derives its strength from being stood on end, IE wall studs. Not laid down horizontally, like floor joists or boat stringers. Good old SYP lumber, or southern yellow pine, is sappy, heavy, and strong, as compared to fir. But it will rot, as will any conifer. It also splits easier, when nailing or screwing. My 2 cents worth. I am going to order cypress to replace my stringers with. KR
