4-LOM wrote:
putting creosote substitute (or something similar) on them once
they're up, but given that they are likely to swell and contract, will
this expose parts of the wood which were previously covered by the
next board and so didn't get coated with cresoste?

I painted liberally with Ronseal Timbercare, and sure enough had
surprisingly large white stripes exposed in Summer so had to do it again.
Incidentally painting was very hard work on the raw boards, so I used a
sprayer the second time. I would consider painting each board before fixing
as that would certainly solve it.

--
Toby.

'One day son, all this will be finished'