Hi,
A few years ago I was in a timber yard when the preservative pressuring tank was opened. The timber pieces inside were simply stacked on top of one another with no separation at all. The ends and sides were stained green alright but I wonder how much had penetrated right into the wood itself?
As for what preservative to use, I suggest you go to a good builders merchants or timber yard and see what they stock. You could ask what their local architects specify.
Treating an already preserved arbour is more a question of appearance than anything else. Just choose a coloured translucent stain that takes your fancy.
Best
A few years ago I was in a timber yard when the preservative pressuring tank was opened. The timber pieces inside were simply stacked on top of one another with no separation at all. The ends and sides were stained green alright but I wonder how much had penetrated right into the wood itself?
As for what preservative to use, I suggest you go to a good builders merchants or timber yard and see what they stock. You could ask what their local architects specify.
Treating an already preserved arbour is more a question of appearance than anything else. Just choose a coloured translucent stain that takes your fancy.
Best
