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


    1 Dig into hillside 2 ft. back from face of retaining wall.
    2 Stretch a level line between wood stakes to establish the wall height.
    3 Dig out dirt along base of wall to accommodate 6 inches of crushed stone.
    4 Add 6 inches of stone, then compact it with a hand tamper.
    5 Add 2 inches of stone dust to create setting bed for base course of blocks; tamp stone dust.
    6 Set and level base blocks; pound each block into stone dust with a rubber mallet.
    7 Use level to align base course with the mason's line.
    8 Backfill behind the base course with crushed stone.
    9 Set the blocks in the second course.
    10 Install a filter fabric behind the wall.
    11 Apply adhesive to adhere the corner block to the base course.
    12 Continue setting blocks, making sure the grooves fit over the tongues on the blocks below.
    13 Use guillotine splitter to cut rough edge on a cap block to create a corner cap.
    14 Set and glue down the corner cap with both rough edges exposed; allow the block to extend 1 inch over the wall.
    15 Set the remaining cap blocks using masonry adhesive.
    16 Backfill the wall with crushed stone.
    17 Fold down the filter fabric, then add 6 inches of loam.
    • Difficulty: Moderate to hard
      What do expect from a project that requires digging dirt and hoisting heavy concrete blocks?
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      Video Directory

      Selected Topic/Section

      Tools List

      • square shovel
      • mason's line
        Mason's line,
        used to establish wall height
      • leveling rod
        Line level,
        used to level mason's line
      • 100-foot tape measure
        Measuring tape
      • tamper
        Hand tamper,
        used to compact crushed-stone base
      • hand rake
      • wheelbarrow
      • two-foot level
        used to check level and plumb blocks
      • mallet
        Rubber mallet,
        used to pound first course into crushed-stone base
      • caulk gun
        Caulking gun,
        used to apply adhesive
      • Guillotine splitter,
        used to cut cap blocks; rents for about $40 to $50 per day

      Shopping List

      1. Retaining wall blocks

      2. Crushed stone

      3. Stone dust

      4. Wood stakes,

      used to support mason's line

      5. Filter fabric,

      used to prevent soil from filling gaps between the blocks

      6. Masonry adhesive,

      used to adhere corner blocks and cap blocks

      7. Loam,

      used to cover crushed-stone at top of wall