I am about to build a retaining wall using sleepers and was just after some advice on a few things. I have read over this forum and found many heplful hints but just need a few more.
My wall will be approx 18m long and 800mm high (the soil is just under 700mm high). I'm replacing an old copper log wall which was poorly constructed with no drainage (which I found out once I pulled it down). Of course I want to do it cheaply so I have been looking at all different sizes of sleepers to see which one would suit.
At first I thought of using 200x50x2.4 sleepers for the wales and 200x75 for the posts which would be set at 1.2m apart. But then I looked at using 200x75 sleepers all round.
To make the posts even over the 18m each post would be set at around 2.25m. Would 75mm sleepers be thick enough to not warp if the posts were 2.25m apart (to save costs) or would I need to set the posts 1.1m apart? I thought of doing that with the 50mm sleepers but most specifications recommend posts at 1.2m apart (using the 2.4m sleepers). So I thought the 75mm sleepers would be better to use.
Also we are planning on putting in an above ground pool next to the wall. Then possibly a deck above the wall. Would I need to coat the wall in some sort of protection against pool water whether it was chlorinated or salt water?
Any advice would be appreciated.