In article ,
PeterC writes:
For about 7 - 8 yeras I've been using a product from Wickes It states that
the VOC content is "very high", so it's probably OK.
I use it mostly on a shed made from plywood and apply it all over (on the
sed, not myself!) every 3 years.
I like the solvent-based, soak-in type, as there's no coating to degrade or
to be rubbed off before renewing. Having said that, for the first 6 months
or so, it is water-repellent.
When renewing a fence, one of the new posts went where an old, rotten post
had been, so I got the hole to the right size then liberally splashed the
preserver all around the hole.
Also, when the posts are in and the Postcrete set, it run some in around the
post. I hope it works.

A friend had a house timber that needed replacing due to wet-rot having
reduced it to something I sucked up with the vacuum cleaner. Nothing
could be done about the damp area at the time which was at one end of the
timber. So I let the replacement timber dry out for weeks, and then stood
in a shallow foil take-away container of cupronol wet/dry-rot protection
in the shed for a few weeks. This wicked up the timber and dried out on
the surface leaving crystals of the active ingredients behind.
It's never gone rotten since (30 years). The only irony is the light
coloured crystal bloom at one end of the timber looks like a nasty fungal
infection, but the timer is still absolutely rock solid if you try
pushing a bradawl into it.

However, I wouldn't do this with outdoor timber. The chemicals would
leach into the soil and might do nasty things to nearby plants, and
to humans who eat any vegetables grown nearby for years to come.

Also, posts outdoors don't rot in the wet ground, or in the air. They
rot only at the bounday where they have both moisture and air exposure.
Having watched workman last week replacing several snapped-off posts
of my neighbour's fence, the soaking wet stumps were just as solid as
the surviving tops of the posts - it was only a 2" length at the soil
boundary that rotted.

--
Andrew Gabriel
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