OTTAWA RETAINING WALLS

Concrete Block Retaining Walls

What is a concrete block retaining wall and why is it popular in Ottawa?

A concrete block retaining wall (segmental block) uses interlocking units built over a compacted stone base with drainage. It’s popular in Ottawa for its clean look, fast installation, and durability in freeze–thaw conditions when built with proper base, backfill, and geogrid.

How thick should the base be for a concrete block wall in Ottawa’s climate?

For most residential walls up to ~1 m, we use 6–8 in of compacted crushed stone for the base, stepped into grade as needed. Taller or loaded walls get a deeper base per engineering and manufacturer specs to handle frost and loads.

Do you install geogrid reinforcement with concrete block walls?

Yes, whenever the height, surcharge (driveways, slopes), or soil conditions warrant it. Geogrid is placed in engineered layers and tied into the compacted backfill to increase strength and stability.

What blocks do you supply and can I mix colours or textures?

We install quality segmental systems from leading Ontario manufacturers in smooth, split-face, and modern textures. You can blend colours or use contrasting caps; we’ll show samples and 3D mockups to match your home.

How do you handle drainage behind a concrete block retaining wall?

We install non-woven geotextile, a perforated drain to daylight or an approved outlet, and a full drainage envelope of clean stone. Proper drainage is essential to prevent winter heave and hydrostatic pressure.

What is the typical timeline for a concrete block wall install?

After the site visit and quote, most 30–50 ft walls up to ~4 ft tall take 3–6 working days. Engineering, permits, complex curves, stairs, or tight access can add time; we’ll provide a clear schedule before we start.

Can a concrete block wall support a driveway or parking pad?

Yes—when designed and engineered for surcharge. We’ll assess loads, specify geogrid and embedment, and coordinate engineering and permits as required by Ottawa or nearby municipalities.

What maintenance do concrete block retaining walls require?

Minimal: keep drains clear, direct downspouts away, avoid using metal blades on caps, and maintain adjacent grading. We provide a care guide at handover to protect your warranty.

Boulder Retaining Walls

What is a boulder retaining wall and where does it work best?

A boulder retaining wall uses large, natural stones stacked on a compacted base with drainage. It’s ideal for rustic aesthetics, waterfront edges, and properties needing robust mass with fewer joints.

How big are the boulders you use and how are they placed?

Typical stones range from 1–5 ft across and 500–4,000+ lb. We machine-set each boulder, keying them into the base and staggering joints for stability, then backfill with clear stone and filter fabric.

Do boulder walls need geogrid or engineering in Ottawa?

For taller walls, slopes, or surcharge conditions, we may add geogrid layers and obtain engineering. We’ll advise based on height, soil, and proximity to property lines or structures.

Can you build smooth curves and steps with boulder walls?

Yes. Boulder walls excel at organic curves and integrated stone steps. We pre-plan the layout and select stones to achieve natural lines and safe step risers.

Are boulder retaining walls suitable near trees or on tight sites?

They can be, but access for equipment and stone size matters. On tight access lots we may recommend smaller armour stone or segmental block to reduce disruption.

How long does a boulder wall installation take?

Most projects complete in 2–5 working days depending on length, height, access, and deliveries. Complex terraces or waterfront logistics may extend the schedule.

What is the cost range for boulder retaining walls in Ottawa?

Costs vary by stone type, transport, height, access, and engineering. We provide fixed pricing after site assessment, with options to value-engineer materials and layout.

How do you manage drainage and soil separation behind boulder walls?

We install a drainage trench with clear stone, perforated pipe to daylight, and non-woven geotextile to keep soils out of the drainage zone.

Blast Rock Retaining Walls

What is a blast rock retaining wall?

Blast rock walls use irregular, fractured quarried stone placed in interlocking courses. They offer a rugged look and excellent mass for larger grade changes.

When is blast rock preferred over armour stone or block?

It’s ideal where you want a natural, rugged aesthetic, need heavy mass, or have budget sensitivity compared with cut armour stone. The irregular shape can reduce material cost while delivering strength.

Do blast rock walls require engineering in Ottawa?

Walls over ~1.0 m high, near structures, driveways, or property lines often require engineered design and permits. We coordinate engineering and approvals for your address.

How do you achieve stability with irregular blast rock?

We bench the slope, key stones into a compacted base, batter the wall, and stagger joints. Backfill is compacted in lifts with geogrid added as specified.

Can you integrate stairs or landings with blast rock?

Yes. We carve step pockets and add stone or precast treads, ensuring safe riser heights and secure landings.

What equipment and access do you need for blast rock?

An excavator and skid steer are typical. We’ll review gate widths, overhead lines, and staging areas to plan safe deliveries and minimize lawn impact.

How do you control drainage for blast rock walls?

We install a perforated drain, daylight outlet, clear stone backfill, and geotextile. Good drainage prevents frost heave and washout.

How long will a blast rock wall last in Ottawa’s climate?

With proper base, drainage, and construction, these walls deliver decades of service. We select durable local stone and provide a warranty with maintenance guidelines.

Poured Concrete Retaining Walls

When should I choose a poured concrete retaining wall in Ottawa?

Choose poured concrete for slim profiles, high loads, or where a smooth or architectural finish is desired. It’s common for tight sites, garages, and stair wells where formwork can be set precisely.

Do poured concrete walls always need engineering and permits?

Typically yes—especially over ~1.0 m or when supporting structures or driveways. We coordinate engineering, rebar schedules, permits, and inspections.

How do you prevent cracking and frost damage in poured walls?

We use engineered footings, rebar reinforcement, control joints, waterproofing, and drainage to relieve pressure. Proper base prep and backfill compaction are critical in Ottawa’s freeze–thaw cycles.

What finishes are available for poured concrete walls?

Options include smooth, light broom, board-form, and architectural liners. We can add cap stones, parge, or veneer to match the landscape.

How long does a poured concrete wall project take?

Forming and rebar typically take 1–2 days, concrete placement a few hours, stripping forms after cure, then waterproofing, drainage, and backfill. Most residential projects finish in 5–8 working days plus cure time.

Can poured concrete walls include steps, rail footings, or guard posts?

Yes. We embed hardware or sleeves for railings, integrate stair runs, and pour pads/footings as part of the scope per the engineer’s details.

How is drainage handled for poured concrete walls?

We install waterproofing membrane, protection board, perforated drain to daylight, and washed stone backfill to control hydrostatic pressure.

What is the cost compared to block or stone walls?

Poured walls can cost more upfront due to forms, rebar, and inspections, but offer high strength and a slim footprint. We provide a detailed quote with value

options.

Allan Block Retaining Walls

What is an Allan Block retaining wall and how is it different?

Allan Block is a branded segmental system with engineered units, corner pieces, and caps. It’s designed for strength, clean lines, and predictable performance when built to spec with geogrid and proper drainage.

Do you follow Allan Block engineering and installation guidelines?

Yes. We build to the manufacturer’s specifications for base preparation, setback, geogrid spacing, and drainage details, and we coordinate engineering when required.

Can Allan Block create curves, corners, and terraces?

Absolutely. Allan Block offers radius blocks, cap options, and corner units that allow smooth curves, tight corners, steps, and multi-tier terraces.

What heights can Allan Block handle without a permit?

Rules vary by municipality, but walls near property lines, supporting loads, or over ~1.0 m often need permits/engineering. We verify requirements for your Ottawa address.

How do you ensure a perfectly level first course with Allan Block?

We laser-grade the base, use screed rails, and check each block in the first course for level and alignment, which controls the entire wall’s accuracy.

What colours and textures are available for Allan Block in Ottawa?

A wide range of natural tones and modern greys with split-face or smooth textures. We provide local samples and recent installs to help you choose.

How long does an Allan Block wall installation take?

Typical 30–50 ft walls up to ~4 ft take 3–6 working days. Engineering, stairs, or terraces can extend to 1–2+ weeks. You’ll receive a clear timeline before we start.

What maintenance is recommended for Allan Block walls?

Keep vegetation out of drain outlets, manage downspouts, avoid de-icing salts on caps, and monitor grade transitions. We include a maintenance checklist at handover.

Gabion Retaining Walls

What is a gabion retaining wall and when is it a good choice?

Gabions are wire baskets filled with rock, creating a permeable, heavy mass wall. They excel where drainage is critical, along waterways, and for modern, industrial aesthetics.

Do gabion walls need foundations in Ottawa?

We install a compacted granular base with geotextile separation and, where required, a concrete leveling pad or deadmen anchors per engineering. Proper base prep prevents settlement in freeze–thaw conditions.

How do you prevent the baskets from rusting?

We use heavy-gauge, galvanized or PVC-coated gabion baskets rated for outdoor longevity. Stone choice and proper installation further extend life.

Are gabion walls environmentally friendly?

Yes. They’re permeable, reduce hydrostatic pressure naturally, and can be planted with vines. Rock infill is locally sourced to reduce transport impacts where possible.

Can gabions be curved or stepped for terraces and stairs?

Yes. We custom-shape baskets, step courses, and integrate stairs or seating. The modular system makes layout changes efficient.

Do gabions require engineering or permits?

Walls over ~1.0 m, near property lines, roads, or waterways commonly require engineering and approvals. We manage design, permits, and conservation authority coordination when applicable.

How long does a gabion project take to install?

Most residential projects complete in 3–7 working days depending on wall length, height, access, and custom fabrication needs.

What’s the maintenance for a gabion retaining wall?

Very low: keep vegetation from blocking outlets, inspect baskets annually, and top up stone only if settlement occurs. We provide a simple maintenance guide.

Planning, Permits & Engineering (Ottawa, Ontario)

Do retaining walls in Ottawa require permits or engineering?

Walls near property lines, supporting structures or driveways, or over ~1.0 m often require permits and/or stamped engineering. We confirm requirements for your address and handle the paperwork.

How do you handle Ontario One Call utility locates?

We request locates before excavation and verify all markings on-site. If private lines are suspected, we can arrange private locates to keep digging safe.

Can you work within conservation or floodplain areas?

Yes—subject to approvals. We coordinate with the appropriate conservation authority, submit drawings, and schedule inspections as required.

What documents will I receive before construction?

You’ll receive a detailed scope, drawings or layout sketches, material specs, start date, and a fixed price. If engineering is required, we include stamped drawings and notes.

Do you survey property lines before building?

We build based on your survey or locate pins. If pins are missing or the line is uncertain, we recommend a surveyor to avoid boundary disputes.

How do inspections fit into the schedule?

If required, we plan base, reinforcement, and final inspections into the timeline and keep you updated on dates and outcomes.

What if groundwater or poor soils are discovered?

We’ll pause, show you findings, and propose remedies such as over-excavation, additional stone, weeping tile, or geogrid. We price changes transparently before proceeding.

Can you design walls to support fences or railings?

Yes. We coordinate post sleeves, embedded footings, or setback adjustments with the engineer to ensure loads transfer safely.

Process, Timeline & Site Logistics

What is your process from quote to completion?

We start with a discovery call and photos, complete an on-site assessment, send a fixed quote and schedule, handle permits/engineering, then build: excavation, base, drainage, reinforcement, wall, caps/finishes, and cleanup. Final walkthrough and warranty close the project.

How quickly can you visit and quote?

Site visits are typically within 2–3 business days; quotes follow in 24–48 hours. Peak season may extend timelines slightly; we’ll advise current availability.

How long does construction take?

Most residential walls up to ~4 ft high complete in 3–6 working days. Complex terraces, stairs, engineering, or tight access can take 1–2+ weeks.

What access do you need for equipment and materials?

A 36–48 in gate is ideal. We protect lawns and hardscaping, use mats when needed, and restore disturbed areas during cleanup.

How do you manage dust, noise, and debris?

We plan reasonable working hours, keep a tidy site, manage dust with water, and remove spoils promptly. Daily cleanup is standard.

What happens if weather delays the work?

We pause during heavy rain or freeze/thaw that would compromise compaction. You’ll receive a revised schedule the same day conditions change.

Do you handle disposal of excavated soil and old materials?

Yes. We load, haul, and dispose at approved facilities, itemized in your quote.

How do you protect adjacent landscaping and structures?

We install temporary barriers, plywood/mats, and precise machine operation. Pre- and post-work photos document conditions.

Materials, Design & Options

Which retaining wall materials do you recommend for Ottawa?

Segmental concrete block and Allan Block suit modern, clean designs; boulders and blast rock deliver a natural look; gabions provide a permeable, modern style; poured concrete fits slim or high-load applications. We recommend based on grade, aesthetics, access, and budget.

Can you match my home’s colours and style?

Yes. We bring samples, propose cap contrasts, and design curves or steps to complement your architecture and landscape.

Do you build stairs, landings, and lighting into walls?

We integrate steps, LED step lights, guard posts, and rail footings per code and manufacturer specs, coordinated with the engineer when required.

How do you handle corners, curves, and terraces?

We design for proper setback, geogrid lengths, and drainage at each tier, using system-specific components for tight corners and smooth curves.

What backfill do you use behind walls?

A drainage envelope of clear stone with non-woven geotextile separation, then engineered backfill compacted in lifts to achieve design density.

Can you tie a retaining wall into new patios or driveways?

Yes. We coordinate base elevations, drainage, and edge restraints so the wall and hardscape perform as one system.

Do you offer 3D concepts or layout sketches?

We provide layout sketches as standard and 3D visuals on request to confirm heights, steps, and finishes before construction.

Are there eco-friendly or low-carbon options?

We can specify locally sourced stone, permeable details, and recycled aggregates where appropriate, balancing performance and aesthetics.

Pricing, Quotes & Payment

How do you price retaining wall projects in Ottawa?

Pricing is based on wall type, height/length, access, excavation/export, base and drainage materials, geogrid, engineering/permits, and finishes. We provide a fixed-price proposal with clear inclusions.

Can you give a ballpark price from photos?

Yes—photos and rough measurements allow a preliminary range. Final pricing follows our on-site assessment and any required engineering.

Do you require a deposit and what are the payment milestones?

A deposit secures materials and scheduling. Progress payments align with milestones like excavation, wall completion, and final walkthrough, outlined in your proposal.

Do you offer value-engineering options?

We often present alternatives—material changes, wall alignment adjustments, or step redesign—to meet budget while maintaining performance.

Are permits and engineering included in the quote?

If required, we include them as line items. We manage the process and keep you informed of timelines and fees.

Do you charge for soil disposal and trucking?

Yes, when applicable. Volumes depend on wall size and site conditions. We show disposal and trucking as separate, transparent items.

Can you work in phases to spread costs?

We can stage terraces or sections, ensuring each phase stands alone safely and integrates cleanly with future work.

Do you provide written warranties?

Yes. You’ll receive a written workmanship warranty and manufacturer information, plus a care guide to protect coverage.

Service Area & Scheduling

What Ottawa areas do you service for retaining wall construction?

We serve all of Ottawa city proper and Ontario communities within a 50 km radius—Kanata, Nepean, Barrhaven, Orléans, Stittsville, Manotick, Greely, Riverside South, Gloucester, Cumberland, Carp, Richmond, North Gower, Osgoode, Metcalfe, Navan, Kemptville, Carleton Place, Almonte, Embrun, Russell, Limoges, and Rockland. We do not service Quebec.

Do you work outside the 50 km radius?

If you’re just beyond 50 km, contact us with your address and photos. Depending on scope and scheduling, we may accommodate with a modest travel fee.

How far in advance should I book?

Peak season fills quickly. Two to four weeks’ notice is ideal, but we keep schedule flexibility for urgent repairs and smaller projects.

Can you coordinate with my landscaper or builder?

Yes. We share elevations, base requirements, and drainage details so adjacent work ties in correctly.

What is the best time of year to build a retaining wall in Ottawa?

Spring through fall is ideal, but we build in colder months when base and drainage can be protected from freeze and saturation. We’ll advise the best window for your site.

How fast can you start after approval?

Site visits within 2–3 business days, quotes in 24–48 hours, and start dates typically 1–3 weeks out, subject to permits and material lead times.

Do you handle emergency stabilization?

We can install temporary shoring, drainage relief, or partial rebuilds to stabilize failing walls, then plan a permanent solution.

How do I get a fast estimate?

Send photos, rough dimensions, address, and any site constraints using our website form. We’ll reply with a quick range and set a site visit.

Care, Longevity & Warranty

How long will my retaining wall last in Ottawa’s freeze–thaw climate?

With proper base, drainage, and construction, segmental, stone, gabion, and poured concrete walls are built to last decades. We follow best practices and manufacturer specs to ensure longevity.

What routine care should I plan for?

Keep drain outlets clear, manage downspouts away from the wall, maintain positive surface drainage, and avoid planting deep-rooted trees too close. Inspect after heavy storms or spring thaw.

Can de-icing salts damage my wall?

Chloride salts can affect concrete surfaces and caps. Use sand or calcium magnesium acetate around walls and steps, and sweep residues off in spring.

What if I notice movement or bulging?

Contact us promptly. Early intervention—drain cleaning, relief trenches, or localized rebuilds—can prevent larger repairs.

Will my lawn and gardens be restored after construction?

Yes. We repair disturbed areas with topsoil and seed/sod or gravel to match the surroundings, included in your quote unless otherwise specified.

Do you offer inspections of existing retaining walls?

We provide assessments with photos and a written plan—repair, rebuild, or replacement—prioritizing safety and cost-effective solutions.

What voids a warranty on a retaining wall?

Unmanaged downspouts, heavy unplanned loads near the wall edge, altered grading that traps water, or unauthorized modifications can void coverage. Our care guide explains how to stay compliant.

Can you retrofit drainage to improve an existing wall?

Often yes. We can add relief drains, regrade, or rebuild sections with proper drainage and geogrid to extend service life.

Ready to Take the Next Step?

We hope that these questions that many of our previous customers have asked, has led you to answers for your own questions. Please feel free to reach out by giving us a call at the number below. If you prefer, you may also submit our online contact form and we'll get back to you asap.