Mike wrote:
I have used treated roofing slats and 75x20mm treated wood,
availble
cheap from Wicks, to make simple benches. These can be taken out
in
the summer what I want to grow tomatoes and cucumbers etc.


I used the same for the staging in Joan's greenhouse. I used the
same
throughout, legs, bearers and slats. As I didn't fancy hammering in
nails in the vicinity of all the glass ;-) and as I didn't fancy
drilling and screwing all the shelf slats, I glued them down with
an
ordinary mastic :-)) 3 years later, no problem :-))

I wholeheartedly endorse the use of treated "two-be-one" sawn
slater's battening for this and innumerable other things. Bang two
together in an L-section, and you've got a surprisingly stiff chunk
of timber: add a third, and it's as good as 4x2 for many jobs (the
centre of a length of wood, I understand, serves little engineering
purpose). This way you don't have to worry about how much of each
size to order, and it comes out cheaper. Easy to handle, too.

The last shed I built was on a flimsy 2x1 frame which went rock solid
when skinned with exterior ply: good for fifty or a hundred years,
I'd say, like a pump-house I built on the same principle but skinned
with aluminium.

Mike.