In this video, This Old House landscape contractor Roger Cook explains how to build a retaining wall using concrete blocks.

Project details

Skill

Cost

Estimated Time

Steps to Building a Retaining Wall

  • Dig into hillside 2 ft. back from face of retaining wall.
  • Stretch a level line between wood stakes to establish the wall height.
  • Dig out dirt along base of wall to accommodate 6 inches of crushed stone.
  • Add 6 inches of stone, then compact it with a hand tamper.
  • Add 2 inches of stone dust to create setting bed for base course of blocks; tamp stone dust.
  • Set and level base blocks; pound each block into stone dust with a rubber mallet.
  • Use level to align base course with the mason’s line.
  • Backfill behind the base course with crushed stone.
  • Set the blocks in the second course.
  • Install a filter fabric behind the wall.
  • Apply adhesive to adhere the corner block to the base course.
  • Continue setting blocks, making sure the grooves fit over the tongues on the blocks below.
  • Use guillotine splitter to cut rough edge on a cap block to create a corner cap.
  • Set and glue down the corner cap with both rough edges exposed; allow the block to extend 1 inch over the wall.
  • Set the remaining cap blocks using masonry adhesive.
  • Backfill the wall with crushed stone.
  • Fold down the filter fabric, then add 6 inches of loam.

Tools

Related

Retaining Wall Ideas

Engineering a Retaining Wall

How to Build a Timber Retaining Wall

Tools & Materials

  • Shovel
  • Mason line
  • String level
  • Tape measure
  • Hand tamper
  • Garden rake
  • Wheelbarrow
  • Level
  • Rubber mallet
  • Caulk gun