Saxman wrote:

On 05/03/2014 07:36, Andy Burns wrote:

Looking at using new untreated oak sleepers direct onto topsoil, or
should I consider treated softwood instead?

Scaffold boards lined with some waterproof material?

I did wonder about lining the beds, either with weed membrane, or full
damp-proof membrane stuff. Most scaff boards I've seen look a little
"tatty".

The sleepers I'm looking at are actually half thickness at 200x50mm so
more like chunky boards anyway, I thought that would be strong enough,
and I'd fix the top board horizontally rather than vertically to make a
sturdier rail for parking bums on.

My question was more about the rot resistance of untreated oak v.s.
treated softwood.