Question 1

What materials are best for retaining walls in Fredericton's climate?

Accepted Answer

In our 37 years of experience, high-density precast concrete interlocking blocks are the most reliable and popular choice for Fredericton. They are engineered to have very low water absorption rates, which makes them highly resistant to cracking and degradation during our harsh freeze-thaw cycles. Natural stone, such as granite or armour stone, is another excellent, long-lasting option that offers a timeless aesthetic. While pressure-treated timber can be a more budget-friendly choice for smaller, non-critical walls, we find its lifespan is significantly shorter (15-25 years) in our damp climate compared to the 50+ year lifespan of properly installed masonry retaining walls.

Question 2

How long does a professionally installed retaining wall last?

Accepted Answer

The lifespan of a retaining wall is directly tied to the quality of its construction, especially its drainage system. A wall we build using interlocking blocks or natural stone, complete with a proper gravel base and French drain system, is engineered to last for 50 to 100 years or more. Hydrostatic pressure from trapped water is the number one cause of premature failure. By effectively managing this pressure, we ensure the structure remains stable and resists the forces of frost heave. In contrast, a timber wall, even when properly treated, will typically require replacement within 15 to 25 years due to inevitable rot and decay in our local climate.

Question 3

Do I need a permit for a retaining wall in Fredericton?

Accepted Answer

Yes, in many cases a permit is required. According to City of Fredericton by-laws, a building permit is typically necessary for any retaining wall that is over 1.2 meters (approximately 4 feet) in height at any point. Permits may also be required for shorter walls if they are supporting a significant load, such as a driveway or a steep slope. As part of our service, we assess the project requirements and, when necessary, we manage the entire permitting process on your behalf. This includes coordinating with engineers to get stamped drawings to ensure your new wall is fully compliant with all local building codes and safety standards.

Question 4

How do you prevent retaining walls from collapsing or bulging?

Accepted Answer

Preventing failure is all about managing water and building a strong foundation. We combat hydrostatic pressure, the primary cause of bulging, by installing a multi-layered drainage system. This includes a deep column of clear drainage stone directly behind the wall, a geotextile fabric to prevent soil from clogging the stone, and a perforated weeping tile (French drain) at the base to channel water away. For the foundation, we excavate below the frost line and build up a deeply compacted granular base. For taller retaining walls, we also integrate layers of geogrid reinforcement that extend back into the slope, creating a stable, unified soil mass.

Question 5

Can a retaining wall fix erosion problems on my sloped yard?

Accepted Answer

Absolutely. This is one of the primary functions of retaining walls. By creating a solid, structural barrier, the wall physically holds back the soil, preventing it from washing away during heavy rainfall, which is common in Fredericton. Our designs go a step further by incorporating effective stormwater management. The drainage systems we install behind the wall collect and redirect subsurface water that would otherwise cause soil saturation and erosion. This provides a comprehensive solution for slope stabilization, protecting your property's foundation and creating a more stable, secure landscape for years to come.

Question 6

What is the difference between interlocking blocks and natural stone?

Accepted Answer

The main differences are aesthetics, uniformity, and cost. Interlocking blocks are precision-engineered for a consistent size and shape, which allows for a very efficient and strong installation with tight tolerances. They come in a wide variety of colors and textures. Natural stone, like armour stone, offers a more organic, unique appearance, as no two stones are identical. It is extremely durable but is typically more expensive due to the material cost and the higher level of skill and labor required for a proper fit and finish. Both are excellent choices for building long-lasting retaining walls when installed correctly.

Question 7

Can a retaining wall create a flat, usable space in my yard?

Accepted Answer

Yes, creating usable space is a key benefit. If you have a sloped property, we can construct one or more retaining walls to create level tiers. This technique, known as terracing, can transform an unusable hillside into functional areas for patios, play areas, or terraced gardens. By strategically placing the walls, we can solve your soil erosion problems while also significantly increasing the functional square footage of your property. This is an excellent opportunity to integrate our garden design services to create beautiful and practical new outdoor living areas.

Question 8

How deep do you have to dig the foundation for a wall?

Accepted Answer

The foundation depth is critical for stability, especially with our frost. For most pedestrian retaining walls, we follow a general rule of thumb: the buried base material should be equivalent to at least 10-15% of the total wall height. For a 4-foot (1.2m) wall, this means excavating for a minimum of 6-8 inches of compacted gravel base. However, for walls supporting heavy loads or built on poor soil, we may need to excavate deeper, sometimes below the frost line, to ensure the footing is on undisturbed, stable ground. A proper foundation prevents the heaving and settling that can destroy retaining walls over time.

Retaining walls in Fredericton

About Our Retaining Wall Services in Fredericton

Our Retaining Wall Process

Site Assessment

Design & Permitting

Excavation & Base

Wall Construction

Why Choose Us for Retaining Walls?

How Much Do Retaining Walls Cost in Fredericton?

Recent Retaining Wall Projects in Fredericton

Retaining Walls FAQ in Fredericton