How to Choose the Right Type of Retaining Wall for Your Property

Retaining wall choice comes down to four factors: how high the wall needs to be, what the soil conditions are like, what your budget is, and what the wall needs to look like. Every other consideration flows from these four.

This guide walks through the decision process we use when we're advising homeowners across Burnaby on what type of wall to build. By the end, you should have a clear enough picture to have a useful conversation with a contractor — and to recognize if they're recommending the right wall for the wrong reasons.

Start With Wall Height

Wall height is the most constraining factor in the selection process. Different wall types have practical height limits beyond which they require engineering, special measures, or simply don't make sense.

Under 600mm (about 2 feet): Any material works. This is landscape wall territory — timber, stone, standard block, even landscape edging systems. These walls are retaining very little, the structural demands are minimal, and the choice is almost entirely aesthetic.

600mm to 1.2m (2 to 4 feet): Still a wide range of options, but you're getting into territory where drainage becomes more important and wall construction technique starts to matter. Concrete block, interlocking block, natural stone, and timber with deadmen are all appropriate.

1.2m to 2.4m (4 to 8 feet): This is the range where you'll need a building permit in Burnaby, and where engineered interlocking block systems (with geogrid) and reinforced concrete block come into their own. Natural stone works but is expensive at this height. Timber is not ideal — deadman systems can be engineered to this height but timber integrity over the wall's life at these heights is questionable.

Above 2.4m (8 feet): You're in engineered wall territory. Geosynthetic reinforced segmental walls, poured concrete cantilever walls, or soldier pile systems, all requiring stamped engineering drawings.

Understand Your Soil

Soil conditions affect the wall design, not just the material choice. But they should also inform the material decision.

Sandy, well-drained soils: relatively easy for all wall types. Lateral earth pressure is lower (sandy soils have higher internal friction angles), and drainage through the soil is good. Most wall types are appropriate.

Silty or loamy soils: moderate lateral earth pressure, moderate drainage. Most wall types work with proper drainage behind the wall.

Clay-heavy soils (common in much of Burnaby): this is the challenging case. Clay soils have high lateral earth pressure when saturated (wet clay is heavy and has high plasticity). They also have low permeability — water sits in them rather than draining through. Walls in clay soil must be designed for worst-case saturated conditions and must have excellent drainage.

For clay soil conditions, we favour wall systems that are well-documented in their load capacity — engineered interlocking block or reinforced concrete block — over materials where the structural capacity is harder to verify (like dry-stack stone in significant heights).

Match the Material to the Aesthetic

Once the structural requirements are met, aesthetics should drive material choice. A wall that holds but looks wrong has failed in the other half of its job.

Pacific Northwest residential landscapes — particularly the older, more established neighbourhoods of Burnaby, Vancouver, and North Vancouver — tend to work well with natural materials. Natural stone, in either dry-stack or mortared construction, looks completely at home in these settings. Timber, where it's not the right structural choice, is at least aesthetically appropriate for cottage-style and vegetable garden settings.

More modern properties, particularly those with contemporary architecture, work well with clean-line concrete block, smooth-face split-face block, or gabion walls with their industrial-natural aesthetic.

Interlocking block systems come in a wide range of face textures and colours — from natural tumbled stone finishes to clean geometric faces. They're visually flexible enough to suit most residential settings.

Don't just pick what's cheapest — pick what's right for the visual context of your property.

Budget Realities

Budget matters, and we won't pretend otherwise. But the budget conversation should include the full lifecycle cost, not just the up-front installation cost.

A timber wall at $250/lm that needs replacement in 20 years might cost more, in net present value terms, than a concrete block wall at $450/lm that lasts 50 years. If you're staying in the property for 30+ years, the longer-lasting material is usually the better financial decision.

If budget is genuinely constrained, there are ways to get good value without compromising on the essential elements (drainage, adequate footing, correct materials). A shorter wall, more terracing to reduce individual wall heights, or phasing the project are all legitimate approaches. We'll work with your budget and tell you honestly what we can and can't deliver within it.