How to Build a Retaining Wall: A Step-by-Step Installation Guide
How to Build a Retaining Wall: A Step-by-Step Installation Guide
Retaining walls are one of the best ways to manage slopes, create level areas, and add structure to your landscape. Whether you’re building a small garden wall or a larger retaining wall to support a raised yard, proper installation is critical for long-term stability and performance.
This guide walks you through a professional retaining wall installation method, focusing on base preparation, drainage, reinforcement, and proper backfill. For manufacturer diagrams, specs, and system-specific requirements, we recommend reviewing Belgard’s official installation resources linked near the end of this article.
If you’re still choosing materials, browse our retaining wall blocks and wall systems here:
👉 Shop Retaining Wall Blocks: https://directlandscapesupply.ca/collections/walls
(Update this link if your wall products live under a different collection.)
Why Proper Retaining Wall Installation Matters
Most retaining wall failures happen because of poor base preparation or inadequate drainage. Water pressure behind a wall can cause bowing, cracking, and eventual collapse. A properly built wall uses a compacted base, free-draining backfill, and reinforcement where required to resist soil pressure over time.
Step-by-Step Retaining Wall Installation
1) Plan the Wall Layout & Height
Mark the wall location using string line or marking paint. Confirm wall height, length, curves, and any grade changes. Check local requirements for walls over certain heights and plan drainage behind the wall to prevent water buildup.
2) Excavate the Trench
Excavate a trench wide enough for the wall block depth plus space for drainage stone behind the wall. Dig deep enough to allow for a compacted granular base and to bury the first course below finished grade. Remove soft soils and organic material.
3) Install & Compact the Base
Install granular base material in the trench and compact thoroughly with a plate compactor. The base must be level front-to-back and side-to-side. This step determines how straight and stable the wall will be over time.
4) Set the First Course of Blocks
Place the first row of retaining wall blocks on the compacted base. Level each block carefully. Take your time here — every course above depends on the first course being perfectly set.
5) Add Drainage Stone & Drain Pipe
Place drainage stone behind the first course of blocks. Install perforated drain pipe at the base of the wall and slope it to daylight or a suitable outlet. Proper drainage relieves water pressure behind the wall.
6) Build Additional Courses
Stack additional courses, following the setback/alignment built into the wall system. Clean debris from the block surfaces before placing each new course so the units seat properly.
7) Install Geogrid Reinforcement (When Required)
For taller walls or walls supporting heavier loads, install geogrid reinforcement at specified courses per manufacturer requirements. Extend the grid back into the retained area and compact backfill over it to tie the wall into the slope.
8) Backfill & Compact in Lifts
Backfill behind the wall using free-draining material. Compact backfill in lifts to reduce settlement and movement. Avoid clay or organic soil directly behind the wall.
9) Cap the Wall
Install wall caps using manufacturer-recommended adhesive. Caps provide a finished look and help protect the wall from water infiltration.
10) Final Grading & Cleanup
Grade the area above and around the wall to direct surface water away from the wall. Clean the wall face and surrounding area. Avoid placing heavy loads near the top of the wall until the backfill has settled.
Common Retaining Wall Mistakes to Avoid
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Skipping proper base preparation
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No drainage stone or drain pipe
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Failing to use geogrid when required
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Poor compaction behind the wall
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Building walls too tall without engineering
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Placing heavy loads close to the top of the wall
Shop Retaining Wall Blocks & Accessories
👉 Shop Retaining Wall Blocks: https://directlandscapesupply.ca/collections/walls
👉 Belgard Wall Systems: https://directlandscapesupply.ca/collections/belgard-collection
👉 Barkman Wall Systems: https://directlandscapesupply.ca/collections/barkman-collection
👉 Newstone Wall Systems: https://directlandscapesupply.ca/collections/newstone-collection
Official Installation Resources (Belgard)
For detailed manufacturer specifications, system-specific cross-sections, maximum heights, and reinforcement requirements, refer to Belgard’s official installation resources:
👉 https://www.belgard.com/plan-design/installation-beyond/installation/