How to Build a Timber Retaining Wall

A timber retaining wall can create a lot of extra space on a sloping block and this is how to build one.

  • Mark out where the wall will go, using a string between two stakes
  • Mark out the spacing between posts, according to the length of the sleepers (1.2 metre intervals for 2.4 metre sleepers or 1.5 metre intervals for 3 metre sleepers)
  • Dig each post hole (300 mm wide X 700 mm deep)
  • Fill the bottom of each hole with gravel to provide drainage
  • Cut the posts to length and seal all cuts with preservative
  • Place the posts in their holes, so that they are leaning about 5 mm towards the slope and fill each hole with concrete
  • Put the sleepers in place one by one and mark and drill where they meet the upright posts
  • Secure each sleeper to the posts with galvanised nails
  • Lay slotted agricultural pipe behind the wall for drainage and surround with gravel
  • Line the back of the wall with porous textile fabric to reduce soil erosion
  • Back fill behind the wall and create a spoon drain to help with runoff
  • Stand back and admire your work!