Posted: 17/04/2017 at 22:32
Have you priced up the costs of railway sleepers plus the men needed to wield them into place and cut them to size? I also think ramming them in behind your wall might just weaken it.
Trellis panels don't curve very easily and also don't last many years - the flimsy cross pieces rot or break in strong winds in my experience.
For a cheaper and more flexible option, I would suggest erecting tall posts to the height of your neighbours' fence panels with about 18"/45cms to 2'/60cms buried in concrete for stability. Fit them round in front of the wall at intervals of 5 to 6'+150cms to 180cms. Before you do that, drill horizontal holes thru them from side to side and at 12"/30cm intervals starting from the top end and working down.
Once the concrete has set leave it to mature overnight and then stretch and tension wires thru the holes. You can then use them to train climbers such as honeysuckle, clematis, roses, campsis; jasmine etc depending on soil, aspect - light levels - and exposure to cold and whether or not you want perfume as well as colour.