What kind of treated timber lasts hundreds of years? When I think of treated timber I’m thinking of Bunnings treated pine... what is the industry standard timber for longevity?
For timber used outdoors, e.g. for making decks pressure-treated timber is used. It's a timber treated with pesticide (chromated copper arsenate). In the past creosote was used to treat things like wooden railroad ties and power poles, but it's no longer used because it's toxic.