How To Landscape Timbers For Retaining Wall

As the main functions of retaining wall to give stronger construction on slope yard and add aesthetical value, timbers come to provide the two functions. If you can landscape them properly, you can support plant bed and howl back an embankment that is mostly unstable in sloped yard. Generally, manufacturers produce landscape timbers in long section of wood that are somewhat thick, frequently 8-by-8 inches. Wood is a natural material that adds warmth and texture. However, untreated timbers may crack, and most types will become discoloured over time. The only drawback of landscape timbers is they have the shortest lifespan if compared to other retaining wall materials, such stone or concrete; a wood retaining wall is still durable, typically lasting 10 to 20 years.

Follow these useful steps to use timbers for building retaining wall!

• Place the first row of landscape timbers in place, 2 inches out from the dugout bank or where you are planning to fill in with a raised natural area.
• Drill 1/2-inch wide holes through the ends of each timber with a hole driller bit and hammer an 18-inch long metal landscape spike through the hole and into the soil. You could also use rebar. The spikes or rebar need to be long enough to go through the timber and 12 inches into the soil.
• Fill in behind the first row of timbers with 2 inches of gravel. Add additional gravel to slope slightly the surface toward one end of the wall with a drop of 1/4 inch for every 4 feet. Place a perforated pipe down on the gravel so that the holes face down. The pipe will remove rainwater from the base of the wall, keeping it relatively dry. Run the pipe the length of the wall and route it out at the end.
• Add a second row of timbers, staggering the ends so that they do not meet at the same point as the first row.
• Drill into the second row of timbers, 2 inches from their ends. Hammer 12-inch spikes through the second row and in to the first to attach them together.
• Fill behind the second row of timbers with more gravel. You want to keep gravel next to the wall so that rainwater will not stay up against it for long, but rather flow down and into the pipe. If the wall is being built for a raised plant area that has yet to be built up, start adding soil at this time, maintaining 2 inches of gravel next to the wall and then soil behind that.
• Add a third row as you did the others and fill in with gravel and soil. Pack the soil down and add more if needed to level the dirt with the top of the third beam.
• Walk 3 feet back on soil side of the retaining wall and dig a trench parallel to the wall that equals the width and height of the landscape timbers. Drill holes along the timbers every foot and then lay the timbers in the trench down the length of the wall. Hammer spikes or rebar though the holes and into the soil.
• Lay down the fourth row of retaining wall, leaving gaps every 6 feet that equal the width of the beams. Place beams in the gaps, so that they are perpendicular to the wall and run back toward the timbers that were buried in the trench 3 feet back.
• Add a fifth and even sixth row to top off the wall, covering the right-angled beams with soil. For shorter walls that are only three rows high, the perpendicular beams are not necessary.