• Retaining walls under 4 feet tall do not need permits in most cities.

• However, for walls exceeding 4 feet in height, a city permit is
  required, along with a design and inspection by an engineer.

• If you need to build a retaining wall taller than 4 feet, we handle the paperwork and secure the
  necessary city approval.

• The process is straightforward, as we collaborate with a structural engineer.
  

• We can also construct retaining walls that support greater elevation changes without needing engineering or permits by tiering shorter walls at a 2:1 ratio. This
  method can sometimes improve both the appearance and functionality of your property

In Lower Mainland and surrounding areas, many homes are built on hills and require retaining walls. Each project is unique, with variations in size, height, and purpose for the retaining walls. Therefore, an on-site visit is necessary to provide an
accurate estimate.

Additional factors include whether the wall supports a load, such as a structure above it.
For walls 4 feet or higher, an engineered interlocking block or concrete wall is required. We can construct pressure-treated wood retaining walls for heights under 4 feet and can build any style of retaining wall to any height.

We offer an extensive selection of interlocking stone block systems and are prepared to present all available choices while offering recommendations tailored to your needs. Additionally, we specialize in installing basalt boulders and stack stone walls. In each case, we seamlessly incorporate comprehensive landscape design elements into the
walls.

There's a wide variety of block styles and color choices available. We utilize Allen Block,
Pisalite, and Valley Stone, each offering multiple sub-brands and color options to
choose from.

If necessary, we can install piping and seamlessly integrate the system into the property's storm drain or as per the site's configuration.

Our process begins with soil excavation followed by the installation of a granite base
and grading. We then proceed with laying the wall's base course, installing drain pipes, granite backfill, filter fabric, soil backfill, and compaction. Certain walls may also require the installation of structural geotechnical elements.

In the Lower Mainland many homes are built on hillsides or mountain slopes. This terrain, combined with heavy rainfall seasons, leads to subgrade water runoff. The accumulation of subgrade water creates hydrostatic pressure (saturated soil like mud) behind retaining walls, which can exert thousands of pounds of pressure per square inch on the structure. Older lumber retaining walls often lack mechanisms to relieve this pressure. Improperly installed retaining walls can fail within a year. Walls with failed or absent drainage systems are particularly prone to collapse. It is crucial to hire a qualified contractor who meticulously constructs every element of the wall. Retaining walls over 4 feet tall pose significant safety and liability risks, which is why the city mandates that a structural engineer oversee and inspect the construction of these taller walls.

When a retaining wall requires engineering, the engineer provides a detailed blueprint of
the chosen wall system, stamps the drawing, and assumes liability for the wall's structure. The engineer conducts site inspections to ensure all elements are installed according to the plan, including geogrid length, granite backfill, filter fabric, drainage system, and the compaction of the base and backfill to the required proctor density.

It is common for neighbouring property owners to share the cost of repairing shared retaining walls and fences. In some instances, hiring a surveyor to determine the exact property line can be practical. The cost of a surveyor is approximately $1000.

If the wall supports a yard elevation and exceeds 2 feet in height, a block wall with core- filled granite is recommended. The cost for walls over 2 feet tall is comparable whether using wood or block, as both involve similar installation work. Wood walls need "dead man" ties, which require excavation, while block walls also necessitate excavation and typically require geotech fabric for anchoring. When hiring a contractor for a retaining wall, it's essential to understand their proposed construction method and the materials they plan to use.

Yes, a failed retaining wall can be a valid home insurance claim, depending on the specific circumstances. Such a failure can pose a significant liability for the property owner, potentially causing additional water runoff onto city or neighbouring properties. When a retaining wall fails on the perimeter of the property, the city often becomes aware quickly and may issue a notice to the property owner to rebuild the wall.