How to Build a Small Retaining Wall With Blocks

What Is a Retaining Wall

A retaining wall is a strong wall that prevents soil from sliding. Its principal responsibility is to ensure that soil does not slope or erode down the slopes. It also maintains the ground level in certain areas, thereby rendering the place safer and more convenient to walk.

Retaining walls are used in homes to level yards and improve outdoor areas. The owners use them to create flat garden beds, define planting areas, prevent erosion, and hold raised sections of the yard.

Concrete Block vs Other Retaining Wall Types

Concrete block retaining wall steps are a popular DIY choice because they are easier to build than many other wall types. The blocks are solid and stiff, and typically made to shape in place. The following is their comparison with other familiar materials:

• Stone walls: Natural stone is pretty; however, it may be more difficult to construct because the stones are uneven and may require expertise to lay well. It may also cost more.
• Wood Walls: Wood (as well as landscape timbers) can be inexpensive to install, but it can rot, warp, or be ruined by insects, which is particularly problematic in damp settings.
• Poured Concrete Walls: These are extremely robust and durable, but they often require forms, mixing concrete, and experience. They are also more expensive and take longer to construct.

Plan Your Retaining Wall Project

Proper planning will make a retaining wall firm and appear attractive. The homeowner is to check the area, measure, and consider the rules and design options before purchasing blocks and excavating.

1. Assess the Site

The retaining wall must be installed where it will solve a specific issue, such as a slope that keeps filling, a garden bed that requires support, or a leveled area. The most appropriate position is where the wall rests on solid ground and water is contained. If this area in your yard directs water, it is smart to address poor yard drainage before you build hardscaping, so the wall does not have to constantly deal with saturation.

Measuring Wall Length and Height

The wall's size should be measured before purchasing materials.

• Length: The total length of the wall to be covered.
• Height: This is the distance between the bottom of the base and the top of the base where the soil will not be permitted.
  

Soil Conditions

The soil influences the wall's stability and the required drainage level.

• Clay Soil: Sustains the water longer, is heavy, and exerts pressure at the back of the wall. It needs strong drainage.
• Sandy Soil: It drains quickly but can easily move when not properly compacted.
• Loamy Soil: This soil is usually stable and easier to plough, yet proper base and drainage are required.

2. Permits and Codes

There are specific retaining walls that require approval from local building authorities. The permit could be necessary in most regions, and where:

• The wall is elevated above ground by more than some height (usually 3-4 feet).
• The wall is supporting a driveway, building, or heavy weight.
• The wall is constructed along property boundaries or sidewalks.
• The wall can impact drainage or adjacent land.

3. Design Considerations

The homeowner has the option of a straight or curved wall, depending on the shape of the yard and the desired result.

• Straight walls are easier to install, gauge, and construct. They are well able to match driveways, sidewalks, and landscape borders.
• Curved walls are more natural in gardens and stronger since the curve distributes the soil pressure. However, curved designs require a more detailed plan and space occupied by blocks.

Materials and Tools Required

The first step is to prepare all materials and tools in advance. With all this prepared, it is quicker and less prone to errors.

Materials

• Concrete retaining wall blocks: Although interlocking concrete blocks are simple to use in DIY walls, they are not the simplest.
• Base and backfill gravel: Crushed gravel provides a solid base and allows the water to seep behind the wall.
• Drain pipe with holes: It lets water out of the wall so pressure does not build up.
• Landscape or geotextile cloth: It prevents soil from mixing with gravel, yet it allows water to pass through.

Tools

• Shovel, String Line, and Stakes: These are used to dig the trench, set up the layout, and ensure the blocks remain straight and level.
• Tamper or Plate Compactor: It is used to compact gravel into hard packs to ensure the wall does not settle.
• Rubber Mallet: It is used to make adjustments to blocks without breaking.
• Tape Measure and Cutting Tool: These will be used to measure and cut blocks as needed.
• Wheelbarrow: It simplifies and speeds up the transfer of blocks of land, gravel, and soil.

Step-by-Step Guide to Building a Small Retaining Wall With Blocks

It is a DIY retaining wall blocks guide that explains the entire process of creating a small block retaining wall with drainage and a finish, from layout, excavation, and finishing.

Step 1: Mark and Prepare the Area

Trace out the path of the wall by means of stakes and string. Make the line straight or weakly curved. A utility-marking service should be called in advance of excavation to avoid striking underground lines.

Step 2: Excavate the Trench

Excavate a trench, 6 to 8 in. wide, more than the blocks, and deep enough to cover the first course half. This foundation course prevents the wall from moving laterally. The bottom of the trench is to be flat and level.

Step 3: Install the Gravel Base

Add 4-6 inches of gravel into the crushed trench. Dump it down to a hand tamper with a plate compactor. The wall weight rests on this base that allows water to drain. Check the gravel level using a level.

Step 4: Lay the First Course

Lay on the hard, rammed gravel the first row of blocks. This is the most crucial row in the project. All blocks should be horizontal at the front and back as well as across. Hammer blocks into the tap with a rubber mallet.

Step 5: Install Drainage

Down behind the first course, place one perforated drainage tube. Cover it with landscape cloth to prevent clogging. Use drainage gravel to cover the pipe. Proper drainage relieves water pressure, which is the primary cause of wall failure.

Step 6: Build Additional Courses

Place the following rows of blocks, interlocking them as bricks to increase their strength. Retaining wall blocks are available with a setback, which causes the wall to incline slightly back. Fill in with drainage gravel and perform light compaction of the backfill after every course.

Step 7: Finish the Top

Stick-on cap blocks with adhesive for low retaining wall construction. Fill behind the wall with soil and level off the area. Shrubs or ground cover on the ground to stabilize soil and enhance appearance.

Drainage: The Key to Longevity

Drainage is the most important part of a retaining wall. Water accumulates behind the wall and forces it. This pressure is called hydrostatic pressure. It can push blocks, tilt the wall, or crack and break.

How to Install a Drain Pipe and Gravel Backfill

When constructing the wall, one of the things that a homeowner must install is drainage, not after.

• On the underside, place a perforated drain pipe directly behind the first layer of blocks.
• Slant the pipe slightly to allow water to drain to the outlet.
• Aim the outlet at some secure place where the water can exit the wall.
• The space behind the blocks should be filled with drainage gravel- clean crushed stone. Instead of pushing the wall, gravel allows the water to be carried to the pipe.
• The gravel layer should be compacted using incremental backfilling to prevent future settlement.

The Role of Landscape Fabric

Add landscape fabric to keep soil from clogging the gravel behind the wall, so water can pass through while fines stay out of the drainage layer. It lets water pass through but prevents soil from mixing into the gravel. Without fabric, soil slowly clogs the gravel and the pipe, weakening drainage over time.

The Bottom Line

One of the simplest methods of preventing soil erosion, even out a sloping surface, and make a yard look better is to construct a small retaining wall out of blocks. It will last longer when constructed properly and provide a more usable outdoor area. If you need dependable materials, tools, and landscaping supplies, Growcycle can provide a variety of backyard retaining wall ideas to facilitate outdoor activities.

Disclaimer: This material is for informational purposes only and should not be relied on for legal, medical, financial, or any other form of professional advice.