Pond Boss Forums GENERAL QUESTIONS Property Projects & Construction Dock Rotting Out In Only 5 Years: Preventable?

First were those screws yellow zinc coated?

Yellow zinc will react with the green PT and rot. Lucky to get four years from them in PT wood. You need to use ceramic coated screws for the new PT.

Do you know the species of wood that is PTreaded? Here in Canada we treat spruce with PT but in most of the US they tread southern yellow pine. Southern yellow pine is a far better PT product because the wood its self resists rot naturally. Only problem I have had with working with southern yellow pine is it is heavy really heavy and most of the time needs to be pre drilled for screws. The screw really likes to follow the grain of the wood. The center of the grain seems to be softer and the screw likes to stick to the softer parts of the tree.

If you want something to really last for ever use Ipe or Jatoba with stainless fasteners and prepare to drill a bunch of holes. Both of these woods are very hard and heavy but will last for ever.

Hope this helps. This is from my experience with decking and stair building for the outdoors.

Cheers Don.