In article ,
David Hill wrote:

I have some tanalised posts that I put in 25-30 years ago, and
are still solid.

I seem to remember that in the "Old days" when timber was tanalised it
was vacuum then pressure treated, but from what I see of modern "Treated
"timber it's just dipped.

It depends. If you buy the proper commercial timber, it's still
treated the same way, but the chemicals are somewhat less nasty
(and possibly less effective). If you buy from a bucket shop,
it's probably just dipped in the stuff sold for putting on fences.

I bought some 6" feather edge boards from B&Q - ye gods, how cheap
and nasty - but I was repairing a cheap, neglected and rotten
neighbour's fence! They were sold as 'treated' and it was clearly
a surface treatment only.


Regards,
Nick Maclaren.