For a low retaining wall, the posts must go 100 mm into the ground for every 100 mm retained above ground. walls higher than 1.5 m will require a building consent. For retaining walls 1 m or higher, the New Zealand building Code may require a safety barrier at the top. in domestic
Wood retaining walls can be substituted for retaining wall blocks construction more cost effectively if the wall is relatively small (no more than 2-3’). Pressure treated lumber of several dimensions can be used to create a wall, planter box or garden border.
When building a retaining wall with wood, you need to determine the size and height of the wall, which, in turn, will depend on the amount of earth mass to be harnessed and the degree of the slope. If there is a lot of earth mass and the degree of the slope high, then the retaining structure will have to be strong enough to hold it back.
Typical Sizes for a Non-boundary, no traffic wall with a 1:10 slope above the wall and 2 to 2.4m of level ground in front of the wall in stiff clay type soil. Square Poles (Small Walls and gardens) Wall Height Sawn Timber Square Pile Size Max Spacing Hole depth Hole Auger Retaining timber 700 1.5 / 100x100 1200 900 300 150 x 50
How to Build a Wood Retaining Wall: 10 Steps (with Pictures)
Step 1, Decide where you want your wood retaining wall to be. Places where water tends to ooze up or stand are not good choices as the water will rot your wall and ruin it rather quickly.Step 2, Clear the area where you want to build your wall of any brush or debris and rake it smooth.Step 3, Cut your 4 by 4 inch (10 by 10 centimeter) posts to the length you want your wall to be plus 18 inches (45.7 centimeters)and set the posts aside.