As with most DIY projects, building a retaining wall is a simple process to outline but requires hard work and dedication. You’ll need everything from pickaxes and shovels to wheelbarrows, sledgehammers, and spirit levels. Plus you must consider the time it will take away from your weekend.
With all this in mind, let’s take a look at how to build a besser block retaining wall.
Step 1: Building the besser block retaining wall
Step 1: Building the besser block retaining wall
- Line up your blocks on the ground in a row and make sure they’re level by using a level.
- Dig down several inches into the ground where you want your first tier of blocks to sit, making sure you dig far enough to support the weight of all three tiers of blocks and soil above them.
Step 2: Digging and preparing the foundation trench
Before you can build a Besser block retaining wall, you’ll need to dig a foundation trench. This will help prevent the blocks from moving or falling due to soil erosion. The following steps will take you through this process:
- Measure the length and width of your planned retaining wall.
- Dig down into the ground at least half as tall as your planned wall (example: if your wall is going to be six feet tall, dig down three feet).
- Line each side of your trench with drainage material such as gravel or crushed stone; this helps prevent water from pooling around the bottom of your foundation trench, which could cause erosion issues over time if not addressed
Step 3: Bed, level and compact the base material (metallic dust, blue metal or crusher dust)
Once the base material is in place, it’s time to bed, level and compact it.
- Bedding: Lay a 2- to 4-inch layer of base material around the entire perimeter of your project area.
- Leveling: Use a laser level or a chalkline and stakes to mark the high spots on your wall where it will be built—usually at least every 5 feet along each side. Using a shovel, fill in any low areas with additional base material until you have a flat surface that is as level as possible. This may take several passes before you are satisfied with how smooth your surface is.* Compacting: Use an old garden rake or similar implement held vertically against one end of the retaining wall while standing in front of it (to avoid damaging any plants or structures that may be nearby). Move briskly back and forth across its length while applying downward pressure on each pass—this will compact the base material underneath your feet into solid mass that resists settling under future weather pressures.* Installing Your Retaining WallOnce all three steps are complete (bedding, leveling & compacting), use concrete blocks on edge with mortar joints pointing inward for structural support for retaining walls up to about 6 feet tall; taller walls should use concrete beams spaced at no more than 3 feet apart along their length instead
Step 4: Lay and level wet concrete in the trench
Once you have finished shoveling the concrete into your trench, you need to use a trowel to smooth out and level it with the surrounding soil. This can be tricky, so make sure that you use a level and measuring tape to check that it is completely even with the ground before laying more blocks on top of it.
Once your entire wall is covered in wet concrete, let it sit for about 30 minutes before adding any more blocks or topping off with dirt.
Step 5: Install your first course of besser blocks on top of your leveled concrete foundation
In this step, you’ll install your first course of besser blocks on top of your leveled concrete foundation. To make sure that each block is level with the ground and every other block in the wall, use a spirit level to ensure that each course is completely level.
To install the first course, put one end of a string line in front of you at waist height and tilt it at an angle so it runs from left to right across all four corners. Then measure three times along this line, moving down about 2 feet for each measurement. This will give you nine measuring points where you’ll place besser blocks spaced evenly apart along the outside edge of the walkway. For example: 3’3” + 3’6” + 3’9” + 4’10” + 5’11”.
Step 6: Build your besser block wall with 10-15mm gaps between each course
- Use a spirit level to check the wall is straight.
- Lay each block on its side, making sure that the gap between blocks is 10-15mm.
- Lay blocks in a staggered pattern for maximum stability and strength.
- Use a brick-on-edge pattern for your besser block retaining wall, as it will help them blend in with surrounding landscaping.
Step 6A (optional): Using pins to join vertical courses
With your vertical courses in place, you’re ready to start attaching them. In order to do this, you will need some pins.
The number of pins needed depends on how long your wall is and how many vertical courses it has. For example, if your wall is 6 inches tall, with two vertical courses (15 blocks), you would want to use 1 pin every 4-5 blocks or so. If the wall was 12 inches tall (3 courses), then you would want to use 2 pins every 6-8 blocks instead.
Step 7: Adding steel reinforcing bars for strength
Reinforcing bars are used to strengthen the wall and make it more durable. They are placed at regular intervals, usually in this case every 10 feet or so.
Reinforcing bars can be used in conjunction with Besser blocks, concrete blocks or even plain old cinder blocks if you want an even stronger structure.
Step 8 (optional): Adding a drainage system behind the retaining wall
You can add a drainage system to your wall if you need to. This is usually required if the soil behind the besser block retaining wall is moist or has standing water.
To add a drainage system, dig a trench across the length of your retaining wall and about 1/2” deep. Line it with landscape fabric or other waterproof material, then fill it with gravel to create drainage channels that allow water to flow away from your wall. Alternatively, you can use corrugated plastic pipe as an alternative method for creating these channels and directing water away from your retaining wall.
Step 9 (optional): Capping the retaining wall using concrete besser blocks with holes.
- Cap the retaining wall using concrete besser blocks with holes.
- Finish the top of the wall by adding decorative stones, a capstone or flat decorative blocks on top of your concrete besser block retaining wall.
- Backfill and clean up after constructing your retaining wall to prevent erosion and runoff issues.
- Maintain your new retaining wall by keeping it free of debris, checking for cracks and repairing them if necessary.
While building a retaining wall is hard work, it’s also satisfying. You’re creating something unique and beautiful that will stand the test of time. As long as you stick to the plan, take your time and do it right, you’ll end up with something you can be proud of for years to come. So what are you waiting for? Get started today.