Thatch roofs don't get damaged by water / rain. I've built bridges in the past that are essentially crisscrossed thatch roofs built through a shallow area and then over top normal wood flooring and then a roof. Don't have to worry about water damage even if the tide goes above the wood flooring.

The X piece does not get water damage either, if what is below it is on land can act as a rain shelter.

https://steamcommunity.com/sharedfiles/filedetails/?id=2823206313

No, natural deterioration never goes below 50%, only if it gets attacked.

Originally posted by electricdawn:

No, natural deterioration never goes below 50%, only if it gets attacked.

Thanks for the reply. I thought so but never really tried to risk it.

Same thing that happens when you don't put a roof over any wood structure, it will go to 50% damage after it gets rained on, until you repair it or put a roof over it. I think round pole fence & Stake wall are exceptions, however.

Angled wood beams as well, funnily. They don't get wet, and anything directly attached to them as well.