retaining wall

Southern Alberta sees a lot of weather extremes — sudden rains, quick snowmelts, and strong winds—all of which can wash away soil quickly. Retaining walls help keep the ground in place, protecting your yard from erosion that can lead to landslides or other damage.

This guide will show you how to construct a retaining wall that’s not only sturdy enough to withstand southern Alberta’s climate challenges but also a stylish statement piece that elevates your outdoor space.

Climate Considerations for Southern Alberta 

These conditions mean that your retaining wall needs to be more than just strong; it needs to be smart. Choosing materials that can handle the freeze-thaw cycle and designing the wall with proper drainage in mind are crucial steps to ensure your wall stands firm against southern Alberta’s weather extremes.

Selecting the Right Materials For Your Retaining Wall

For a retaining wall that lasts, make sure to go for frost-resistant, well-draining materials. Concrete block walls are especially good for this. They’re tough enough to handle the freeze-thaw cycles that can mess with the soil, making them perfect for our climate. Plus, they can be designed to drain water well, which is crucial here, where we get a lot of snow and rain. 

Since concrete blocks come in various styles and sizes, you can easily find something that not only does the job but looks good too. They’ll stand up to southern Alberta’s climate and keep your landscape looking great. For any homeowner in southern Alberta thinking about building a retaining wall, using concrete blocks is a smart, durable choice. 

Now that you know why concrete blocks are the material of choice for retaining walls, you can get started on building a resilient structure for your space.

Step 1: Envision Your Retaining Wall

Start by envisioning where your wall will go. Consider how the sun hits your yard, where water tends to collect, and what part of your garden you want to highlight or support. This foresight ensures your wall not only looks great but functions well too.

Step 2: Design Your Retaining Wall

What look are you going for? Concrete blocks will give you a range of styles, from natural stone to more modern looks. Also, decide on the height and length of your wall. Keep in mind that taller walls might need a professional’s touch for safety.

Step 3: Check Local Regulations

Research local building codes regarding retaining walls. Rules on height restrictions and permits are crucial to ensure your project is compliant and hassle-free.

Step 4: Integrate with Your Landscape

Plan how your wall will blend with your yard’s overall look. It should complement your space, adding both beauty and utility.

Step 5: Clear the Site

Prepare your site by removing any obstacles like plants, rocks, or debris. A clear area is essential for a sturdy foundation.

Step 6: Dig the Trench

Dig a trench that’s not only wide and deep enough for your wall’s base but also accommodates drainage. Here are important considerations for your trench: 

  • The taller your wall, the deeper and wider your trench should be. 
  • In southern Alberta, you’ll want the depth of your trench to be approximately 6 inches below the frost line. 
  • The width of your trench should be at least 12 to 24 inches wider than your wall’s thickness to allow room for both the structural base and the essential drainage system behind the wall. 
  • The space behind your wall will be backfilled with gravel, facilitating water runoff and reducing pressure on the wall. 

Remember, the trench’s dimensions might vary depending on the height and design of your wall, as well as local soil and climate conditions. You may need to adjust these guidelines based on your specific conditions.

Step 7: Level the Base

Compacting the base material in the trench ensures a stable foundation, crucial for the longevity of your wall. Create a level and compact base using gravel or crushed stone. Take your time with this step; an uneven base can lead to a crooked wall or structural issues down the line.

Step 8: Lay the Foundation

For the foundation material, compacted gravel is a top choice. It provides excellent drainage and helps distribute the weight of the wall evenly. Use compacted gravel for a strong, frost-resistant base. Lay a layer of gravel in your trench, then compact it until it’s firm and level. 

Step 9: Place the First Block

Start with the most visible corner or edge. Place the first block in your trench, making sure it’s level from front to back and side to side. This first block sets the stage for the rest of the wall, so take your time to get it right.

Step 10: Install the Remaining Blocks of Your First Row

Continue laying blocks, keeping each level and tight against the previous one. Adjust with a rubber mallet as needed, and consider using construction adhesive for extra stability in cold climates.

Step 11: Check Level Regularly

As you build, use a long level to check that your row is even. Irregularities at the base can amplify as you build up, leading to a crooked wall. Be sure to do this every few blocks for each row you build.

Step 12: Install Your Drainage System

Right after laying the first row of blocks, it’s time to install the drainage system. Incorporating effective drainage solutions is especially important in areas prone to heavy rain or snowmelt. 

  • Lay a perforated drainage pipe at the base of the wall, behind the first row, ensuring it has a slight downward slope towards the intended drainage area. 
  • Cover the pipe with landscape fabric to prevent clogging and then backfill with gravel. 

This setup will facilitate water movement away from the wall, crucial for preventing pressure build-up and ensuring the longevity of your structure.

Step 13: Build Up and Backfill

With each new row, offset the blocks for better stability and backfill with gravel to enhance drainage. Compact the backfilled gravel before adding your next row.

Step 14: Cap the Wall

Finish your wall with capstones, securing them with construction adhesive. Ensure they slightly overhang the blocks below for effective water runoff.

Step 15: Final Touches

Backfill the area behind the wall with soil up to the level of the capstones. Consider landscaping this area with grass or shrubs for added stability and aesthetics.

Maintaining Your Retaining Wall

Regular maintenance ensures your retaining wall withstands the harsh winters and rapid thaws characteristic of southern Alberta. 

Here are some quick tips to ensure your hard work building your retaining wall lasts:

  • Inspect your wall seasonally for any signs of movement, cracks, or bulging, which could indicate drainage issues or frost heave damage. 
  • Keep the drainage path clear of debris to ensure water flows freely away from the wall. 
  • During the spring thaw and after heavy rainfall, check the wall and adjacent soil for any signs of erosion or water pooling.
  • In winter, avoid piling snow against your retaining wall. The weight of the snow and the water from melting snow can exert undue pressure on the structure. Instead, shovel snow away from the wall to a safer location. 

By maintaining diligent care of your retaining wall, you can preserve the integrity and appearance of your landscape investment and enjoy your retaining wall for years to come.