NANAIMO RETAINING WALLS

Frequently Asked Questions

General & Getting Started

What areas do you serve on Vancouver Island?

Nanaimo Retaining Walls serves Nanaimo, Departure Bay, Hammond Bay, North Nanaimo, Cedar, and Lantzville, with selective work in nearby communities. If your site is outside these areas, we will advise on feasibility and any travel considerations.

How do I get a quote from Nanaimo Retaining Walls?

Please email or upload site photos, approximate wall height and length, the site address, and your preferred material. We then conduct an on-site assessment and provide a clear, fixed-price quotation outlining scope, timeline, and payment milestones.

What is your step-by-step process?

Our process is designed for clarity and compliance: discovery call → on-site assessment → fixed quote → BC One Call utility locates → permits/engineering if required → excavation and base preparation → drainage and geogrid installation → wall construction and capping → final cleanup and homeowner walkthrough. Each stage includes quality checks and documented approvals where necessary.

How long do projects typically take?

Smaller walls under ~0.6 m generally require 2–4 days. Mid-size segmental projects often complete in 1–2 weeks, while engineered or limited-access sites may take 2–4+ weeks. Weather, inspections, and material lead times can influence schedules; we issue a milestone calendar before work begins.

Do you handle permits and engineering in Nanaimo?

Yes. Where wall height, loading, or location triggers requirements, we coordinate engineer-stamped drawings and guide you through City of Nanaimo permitting. Our team manages submittals and inspection scheduling to keep the project compliant and on schedule.

How do you build for Nanaimo’s wet climate?

We employ a compacted granular base, set the first course below grade, and install perforated drain piping to daylight or a sump. Walls are backfilled with free-draining aggregate wrapped in filter fabric, reinforced with geogrid as required, and finished with grading that directs surface water away from the structure.

What payment terms do you offer?

Projects are typically invoiced with a deposit to schedule, progress payments at agreed milestones, and a balance on completion after the walkthrough. Exact percentages are set out in your written quotation and contract.

What warranties do you provide?

We provide a written workmanship warranty (placeholder: 3 years, update to your policy) and pass through manufacturer material warranties. Exclusions generally include abnormal ground movement, flooding, third-party alterations, or inadequate surface drainage.

Concrete Block Retaining Walls

(CMU/ Segmental)

What is the difference between CMU and interlocking (SRW) block?

CMU walls are built on reinforced concrete footings and may include steel reinforcement and grout for structural capacity. Interlocking segmental retaining walls (SRW) use modular units on a granular base with mechanical setback and geogrid to create a reinforced soil mass.

When is concrete block the best choice in Nanaimo?

Concrete block is recommended when you require durable performance, clean architectural lines, and efficient installation across a range of heights. It offers strong value for residential and light-commercial projects and is widely available from Vancouver Island suppliers.

How high can a concrete block wall be?

Heights range from low garden edges to multi-metre walls when properly engineered. Final allowable height depends on soils, surcharges (e.g., driveways), and the reinforcement design.

Do concrete block walls require a footing?

CMU walls typically require an engineered reinforced footing. SRW systems rely on a compacted granular base and a buried first course to resist sliding and overturning, with geogrid added per design.

What colours and textures are available?

Local suppliers stock a broad palette of colours with split-face, smooth, and architectural textures. We can present samples during design to align with your landscape and home exterior.

How are taller block walls reinforced?

SRW designs use geogrid at specified intervals to tie the wall face to the retained soil. CMU designs use steel reinforcement and grout cells, with details set by the engineer.

Can stairs and lighting be integrated into block walls?

Yes. We can integrate matching steps, landings, and low-voltage lighting to create a cohesive and functional landscape.

What maintenance do block walls require?

Annual maintenance is minimal: keep surface grading correct, ensure drains and weep paths are clear, and avoid imposing heavy loads at the wall crest. Promptly address any settlement adjacent to the wall.

What lifespan should I expect?

When designed and built correctly, concrete block retaining walls routinely last 25 years or more in coastal climates. Proper drainage and maintenance extend service life significantly.

Poured Concrete Retaining Walls

When is a poured concrete wall appropriate?

Poured concrete is ideal where a narrow footprint, modern aesthetic, or specific structural capacity is required—such as supporting railings or fences at the crest. It also suits tight sites where modular units would be impractical.

Do poured concrete walls crack?

Concrete can develop hairline cracking; this is managed through rebar placement, control joints, proper curing, and robust drainage. Structural cracking is uncommon when the wall is engineered and constructed to specification.

Do poured walls require footings and reinforcement?

Yes. Poured walls are typically built on engineered reinforced footings with vertical and horizontal rebar to resist lateral earth pressures and surcharge loads.

What finish options are available?

Finishes include smooth, broom, exposed aggregate, and architectural form-liner patterns. Walls can be parged or clad with stone or brick veneer for additional texture and colour.

How tall can a poured concrete wall be?

Heights range from low retaining edges to several metres with appropriate engineering. The final design considers soils, loads, and site constraints.

How is drainage provided for poured walls?

We install footing drains, weep holes, and clear-stone backfill, with waterproofing or damp-proofing specified as conditions require. Finished grading directs runoff away from the wall.

Can poured walls be curved?

Yes. Curved walls are achievable with custom formwork. We will discuss radius limitations and pricing during design.

What impacts should I expect during forming and pouring?

We coordinate concrete deliveries, manage noise and site access, and protect adjacent landscaping and surfaces. Washout and cleanup are handled in accordance with environmental best practices.

When can the wall be backfilled or loaded?

Initial curing typically allows controlled backfilling within 3–7 days, while full design strength is reached at approximately 28 days. We will advise based on mix design and weather.

Gabion Retaining Walls

What is a gabion retaining wall?

A gabion wall is constructed from heavy-duty wire baskets filled with stone, creating a permeable structure that retains soil while allowing water to pass through. The result is a durable system with a contemporary, natural appearance.

Why choose gabions in Nanaimo?

Gabions perform exceptionally well in wet climates because they relieve hydrostatic pressure by design. They adapt to irregular terrain, can use locally sourced stone, and are well-suited to coastal aesthetics and erosion-control applications.

What basket sizes are available?

Typical modules range from 0.6–0.9 m deep, 1–2 m long, and 0.5–1 m high. We stack and step the baskets to achieve the required height and embed the base course for stability.

Do gabion walls require engineering?

Engineering may be required when heights, loads, or proximity to property lines trigger regulatory thresholds. We confirm requirements at the site visit and coordinate any needed stamped designs.

How are gabion walls constructed?

We prepare a compacted base, assemble and anchor baskets, install filter fabric behind the wall, and place stone in controlled lifts to ensure uniform compaction and appearance. Final grading manages surface runoff and protects the toe from scour.

Are gabions suitable near water features?

Yes. With appropriate scour protection and design, gabions are effective for erosion control adjacent to streams, ponds, or swales. We assess site hydraulics before recommending this option.

Can existing gabion walls be repaired?

In many cases, yes. We can replace or re-tension damaged baskets, top up displaced stone, and improve drainage or scour protection to restore performance.

What maintenance is expected?

Maintenance is limited to removing debris and vegetation that could trap moisture and periodically inspecting baskets for damage or corrosion. Stone infill is highly durable and typically maintenance-free.

Boulder Retaining Walls

Why select a boulder retaining wall?

Boulder walls offer a natural West Coast appearance, rapid installation, and excellent drainage characteristics. They are ideal for terracing sloped yards and integrating planting pockets and natural steps.

How tall can a boulder wall be?

Boulder walls can range from small garden tiers to higher, engineered systems, depending on stone size, soils, and surcharge conditions. Engineering is recommended as heights increase or loads are present.

What types of stone do you use?

We source durable local stone—often granite—sized appropriately to the design. Stone selection balances stability, appearance, and availability from Island suppliers.

How is stability achieved?

Stability is achieved through a compacted base, buried courses, interlocking stone placement, and proper drainage. Engineering is provided for taller walls or when adjacent structures impose additional loads.

Can steps and planting pockets be integrated?

Yes. We can incorporate stone steps, terraces, and planting pockets to create functional access and visual interest that blends with the landscape.

Are boulder walls environmentally considerate?

They use natural materials, promote drainage, and can reduce embodied carbon when stone is locally sourced. We also minimize site disturbance through careful access planning.

Are boulder walls suitable for precise, straight lines?

Boulders are best for organic alignments. If your project requires tight tolerances or a narrow footprint, we may recommend block or poured concrete.

What maintenance is required?

Maintenance is minimal and typically limited to vegetation management and keeping water paths open. We advise periodic visual inspections after major storms.

Retaining Wall Repair & Replacement

Do you repair existing retaining walls in Nanaimo?

Yes. We repair leaning, bulging, cracked, or poorly drained walls across all material types. Our recommendations are based on a site-specific inspection and the wall’s remaining service life.

Can a leaning wall be repaired without full replacement?

In select cases, yes. Localized rebuilding, additional drainage, and geogrid can stabilize some failures; however, significant structural movement usually warrants replacement for safety and longevity.

Do you replace timber or railroad-tie walls?

Frequently. We upgrade aging timber systems to SRW block, boulder, poured concrete, or CMU solutions that provide superior durability and safety.

How do you diagnose wall failure?

We review soils, drainage paths, base construction, geometry, and surcharge loads such as driveways or structures. Findings are documented and used to determine whether repair or replacement is the prudent option.

Can I increase the height of my existing wall?

Increasing height changes loading and often exceeds the original design capacity. We typically recommend an engineered rebuild or a terraced approach to achieve the required elevation safely.

How do you correct poor drainage behind an existing wall?

We install perforated drains and weep paths, replace cohesive soils with clear stone where feasible, add filter fabric, and regrade surfaces to direct water away from the wall.

What will repair or replacement cost?

Pricing depends on wall length and height, access, disposal of existing materials, drainage upgrades, chosen material, and any engineering or permits. After inspection, we issue a fixed, written quote with inclusions and exclusions.

How quickly can emergency conditions be addressed?

Unsafe conditions are prioritized. We can provide temporary shoring or erosion control and schedule permanent works promptly once locates, engineering, and approvals are in place.

Policies, Access & Site Care

Do you arrange BC One Call utility locates?

Yes. Utility locates are requested before excavation to ensure safe and compliant operations. We coordinate timing to avoid project delays.

How do you protect my property and adjacent areas?

We use ground-protection mats, maintain clean access routes, and implement dust and noise controls. Daily cleanup is standard, and we coordinate with neighbours or property managers when required.

What if site access is limited?

We plan for compact equipment, staged deliveries, or hand methods as needed. Limited access can affect cost and schedule; these impacts are identified in your quotation.

Do you remove and dispose of an existing wall?

Yes. Demolition, responsible disposal, and recycling where possible are included unless otherwise stated. We restore the site to a clean and safe condition at project end.

Can you match existing colours and textures?

We will source the closest available match from local suppliers. Exact matches depend on the age and availability of legacy products.

What information helps you quote faster and more accurately?

Please provide your address, preferred material, approximate height and length, clear site photos (including access), and any surveys or previous engineering. This information reduces design time and change orders.

Maintenance, Warranty & Aftercare

What routine maintenance do you recommend?

Maintain positive grading away from the wall, keep drains and weep paths free of debris, and avoid storing heavy items at the wall crest. A brief annual inspection after the rainy season is advisable.

How should I care for the wall during the first year?

Monitor for settlement at adjacent soils, confirm water is draining as intended, and report any unusual movement or pooling. Early attention prevents minor issues from becoming major concerns.

What conditions may void a warranty?

Warranty coverage may be voided by abnormal ground movement, flooding, vehicle impact, unapproved modifications, or inadequate surface drainage and maintenance. Full terms are provided with your contract.

Do you offer seasonal inspections?

Yes. We offer optional maintenance check-ups to clear drains, review grading, and identify any developing issues. This service helps maximize the wall’s lifespan.

Where can I find quick answers before scheduling a visit?

Our FAQs Hub and homepage FAQs address common questions about process, permits, timelines, drainage, pricing, and warranties. For site-specific advice, please contact Nanaimo Retaining Walls to arrange an assessment.