Armour stone is the most durable, lowest-maintenance way to shape a sloped or settling Ottawa landscape — and getting it right depends entirely on the base beneath it, the drainage behind it, and the crew that places every block.
Call (613) 324-9141 — no cost, no obligation
Built once — built to outlast the house behind it
Armour stone is large-format natural quarried limestone — individual blocks that commonly weigh from roughly 750 pounds up to two tonnes or more. Because each stone carries enormous mass, a wall built from it does much of its retaining work through sheer weight and interlock rather than mortar. That is its great advantage and its great risk: placed correctly on a proper base, an armour stone wall can outlast the house behind it; placed carelessly, gravity that should be working for you starts working against you.
We are not a general landscaping outfit that builds the occasional wall between mowing contracts — armour stone retaining walls, garden walls, steps, and stone features are what our crews do every working day across the region. Years of hands-on work in Ottawa soils and Ottawa winters shape every decision we make on site, from how deep we dig the base to how we vent water out from behind the face.
Specialization matters more in this trade than in almost any other branch of landscaping, because the failure mode is slow and expensive. A wall that was never properly drained does not fall over on day one. It leans a little after the first wet spring, a little more after the first hard freeze, and three or four winters later the homeowner is paying to tear out and rebuild what should have been done once. We build it once.
Every advantage here is something we do on every job — not a credential, a process.
Retaining walls, garden walls, steps, and stone features are our entire focus, not a sideline. The crew that shows up has set thousands of stones, and it shows in how square, how level, and how tight the finished face sits.
When your wall crosses the threshold that triggers a City of Ottawa building permit, we manage the application, drawings, and inspection coordination through the City’s process so you are not left navigating it alone.
Ottawa’s freeze-thaw cycle is the single most destructive force acting on any wall here. We build below the frost-affected zone on a compacted granular base, with drainage designed to keep water from collecting, freezing, and expanding behind the stone.
The base is laser-leveled and compacted before a single block is placed, drainage stone and geotextile go in as the wall rises, and each stage is checked before the next begins. The most important part of any wall is the part you never see.
For walls that cross the engineering threshold under the Ontario Building Code, design by a Professional Engineer (P.Eng.) is included in your project scope — sealed drawings specifying dimensions, drainage, and foundation requirements.
After an on-site assessment you receive a written, fixed-price quote — not a vague range that creeps upward mid-build. A written warranty is delivered on project close-out, and all project documentation is available on request.
Every service is quoted from a written, fixed-price estimate after an on-site assessment. Ranges are indicative only, benchmarked against published 2025–2026 Ontario-market pricing.
The core of what we build. An armour stone retaining wall holds back a slope or a raised grade using the mass and interlock of large quarried blocks, seated on a compacted granular base with drainage built in behind the face. We size the base depth, block weight, and drainage to the height of your wall and the load it carries.
Lower walls — typically under one metre of exposed height — used to terrace a yard, define a planting bed, or carve a flat usable space out of a slope. These usually sit below the permit threshold but still live or die on their base and drainage. Even a low wall that skips drainage will heave and shift after a few Ottawa winters.
Solid armour stone treads make steps that will never rot, crack, or wobble loose the way timber and some pre-cast systems do. Each tread is a single quarried block, leveled and seated individually, for a flight that holds firm through every freeze-thaw season.
On a steep grade, two or more shorter walls with a planted bench between them often outperform a single tall wall — both visually and, in some cases, by keeping each tier below the height that triggers engineering. The result is more stable and far better looking.
Weathered-edge armour stone makes a clean, permanent border for a driveway, parking area, or property line — low enough to need no permit, heavy enough that it never wanders. A practical, good-looking way to stop gravel migration and define an edge that stays put.
Armour stone frames ponds, cascades, and water features with a natural, quarried look that engineered block can’t match. Scope and price vary widely with size, pumps, and plumbing; we quote these after seeing the site.
Many of the walls we are called to look at are failing for one reason: water was never given a way out. We assess whether a leaning or bulging wall can be partially reset or whether it needs to come down and be rebuilt on a proper, drained base — and we tell you honestly which one your wall needs.
For waterfront and erosion-prone grades, large armour stone is the standard material for holding a bank against moving water. Shoreline work near water may involve conservation authority approval in addition to municipal requirements; we identify what your specific site needs before any stone is ordered.
The ranges below are indicative only and based on published 2025–2026 Ontario-market pricing. They’re here to help you budget — they are not an offer to contract.
Installed, on a compacted base with drainage built in behind the face. Taller and engineered walls land higher. A standard residential wall around 3 ft high and 30–50 ft long often totals roughly $3,500–$9,000.
3 ft × ~30–50 ft, total
per tread, installed
3–4 steps, typical
per sq ft of face (under 1 m)
at cost, where required
municipal fee, where required
Most of these trace back to the same root cause — water with nowhere to go. We diagnose the real cause before quoting a fix.
The most common call we get. Almost every failing wall in this region failed for the same reason — water had no way out, built up behind the face, and pushed the wall forward, made worse each winter as that trapped water froze and expanded.
A steep grade can swallow a third of a backyard. A properly engineered armour stone wall, or a tiered set of walls, carves flat, usable, plantable space out of a slope that was previously good for nothing but erosion.
Ottawa’s heavy spring melt and summer downpours move a lot of soil. Where grade and water are washing material away, armour stone holds the bank and redirects drainage so the problem stops instead of spreading.
Parking a vehicle, boat, or RV — or building a fence — within a few feet of the top of a wall adds lateral pressure it may never have been designed for. We assess whether your wall can carry the load it’s now being asked to hold, and rebuild to spec if it can’t.
A wall or set of steps built without drainage and without reaching below the frost-affected zone will lift, tilt, and separate over successive Ottawa winters. The cure is building it correctly from the base up — there is no surface patch for frost heave.
Pressure-treated timber walls rot and pre-cast block systems can fail at the joints. Replacing them with armour stone trades a wall with a service life measured in years for one measured in decades.
This is what a properly built armour stone wall actually requires. Hold any contractor you hire to the same list.
Six steps, each with a commitment we control — response time, quote timeline, and the stages we check along the way.
We come out, look at the grade, the soil, the access, and any surcharge loads, and talk through what you want the space to do. No cost, no obligation.
You receive a clear, written, fixed-price quote — not a moving range — with scope, stone type, and what is and isn’t included spelled out.
If your wall’s height triggers a City of Ottawa permit and a P.Eng. design, we manage the application and sealed drawings end-to-end.
We excavate, remove unsuitable soil, and build a laser-leveled, compacted granular base below the frost-affected zone — the foundation that decides whether the wall lasts.
Each block is set, leveled, and interlocked as drainage stone and geotextile go in behind the rising face, with each stage checked before the next.
We walk the finished work with you, deliver a written warranty, and provide project documentation on request. Built once, built to hold.
Armour stone walls, steps, and features across the City of Ottawa and surrounding communities — Ontario only.
We work within Ontario only. If your community isn’t listed and you’re in the greater Ottawa region, call (613) 324-9141 — there’s a good chance we cover you.
The real regulations and conditions that shape every armour stone wall built in Ottawa — with their actual values and names.
Under the Ontario Building Code (O. Reg. 332/12), Clause 1.1.2.2.(2)(c), Part 4 of the Code applies to a retaining wall exceeding 1,000 mm (about 3.3 ft) in exposed height adjacent to public property, access to a building, or private property the public is admitted to. In practice, once an Ottawa wall crosses roughly one metre in those situations, it generally needs a City of Ottawa building permit and a P.Eng. design. Walls below that height typically don’t require a permit but must respect property setbacks.
A retaining wall meeting that threshold is treated as a “designated structure” under Sentence 1.3.1.1.(1) of Division A of the Building Code, which brings it under engineered design and permit review. Engineering fees in the Ottawa market commonly run about $1,000 to $3,000 depending on complexity, soil, and access; the engineer’s sealed drawings specify dimensions, reinforcement, drainage, and foundation requirements.
Where the public has access to open space at the top of a designated retaining wall, the Building Code requires the wall to be protected by a guard on its open sides (Division B references including 9.8.8.1). Whether a guard is required on your wall depends on its height, its setting, and who can access the top — we flag this at the assessment so it’s designed in from the start.
The City of Ottawa accepts building-permit applications online through the My ServiceOttawa Building, Planning and Land Development portal — submit plans, upload documents, pay fees, and book inspections without a trip to a Client Service Centre. Before any excavation, Ontario law requires locating underground utilities through Ontario One Call (1-800-400-2255), a mandatory no-charge service, with several business days’ notice. We handle the permit submission and coordinate locates.
Ottawa is one of the coldest capital cities in the world, and its repeated winter freeze-thaw cycles are the defining design challenge for any retaining structure here. Water that collects behind a poorly drained wall freezes, expands, and exerts enormous pressure on the face; over successive winters that pressure leans, cracks, and ultimately topples walls. Every wall we build is detailed to keep water moving and to sit below the frost-affected zone — the baseline standard for building in this climate.
A surcharge load is any weight resting on the soil close enough to the top of a wall — generally within a few feet — to add lateral pressure: a parked vehicle, RV, boat, shed, or a fence built along the top. Many Ottawa walls fail because they were never designed for a load added later. If you intend to park, build, or store anything near the top of a wall, that has to be part of the design from day one.
Our old timber wall was leaning more every spring. They tore it out, showed us there was no drainage behind it at all, and rebuilt it in armour stone with proper stone backfill. Two winters in, it hasn’t moved a millimetre.
The back third of our yard was a useless slope. They terraced it with two armour stone walls and now we have a flat patio and a garden bed where there used to be erosion. The written quote was exactly what we paid.
What stood out was the base. They spent most of the first day on the part you never see — digging, compacting, leveling — before a single stone went down. You could tell that’s where the real work is.
We needed a permit because of the wall height, and they handled the whole thing with the City and the engineer. We didn’t have to chase a single piece of paper.
The stone steps they built down to our lower yard are solid as bedrock. After a couple of Ottawa winters there’s no wobble, no shifting — nothing like the pre-cast steps they replaced.
Honest assessment. They told us part of our existing wall could be reset and only the worst section needed rebuilding, instead of selling us a full teardown. We appreciated that.
We park our trailer near the top of the new wall, and they designed it for that load from the start. They explained the surcharge issue clearly so we understood why it mattered.
Armour stone is large-format natural quarried limestone — individual blocks that commonly weigh from roughly 750 pounds up to two tonnes or more. Because of their mass, the blocks retain soil through weight and interlock rather than mortar, which is what gives a properly built armour stone wall its long service life.
Installed armour stone retaining walls in the Ottawa market commonly run about $35 to $65 per square foot of wall face, based on published 2025–2026 Ontario pricing. A standard residential wall around 3 feet high and 30–50 feet long often totals roughly $3,500 to $9,000. These are indicative figures only — your actual price is the written, fixed-price quote we provide after an on-site assessment.
Generally, yes — once a retaining wall exceeds 1,000 mm (about one metre) in exposed height adjacent to public property, access to a building, or property the public is admitted to. Under Ontario Building Code Clause 1.1.2.2.(2), Part 4 of the Code then applies, which means a City of Ottawa building permit and engineered design. Walls below that height usually don’t need a permit but must still respect property setbacks.
Walls that cross the one-metre exposed-height threshold are treated as designated structures and require design by a Professional Engineer (P.Eng.). Engineering in the Ottawa market commonly runs about $1,000 to $3,000 depending on complexity, soil, and access. We include the engineering coordination in your project scope.
Built correctly — on a compacted base below the frost-affected zone, with drainage behind the face — an armour stone wall has a service life measured in decades and can outlast the house behind it. The walls that fail early almost always failed because of missing drainage, not because of the stone.
The number-one cause is inadequate drainage. Water builds up behind the wall, creating hydrostatic pressure that pushes it forward; in Ottawa’s climate that trapped water then freezes and expands each winter, accelerating the failure. A wall built with proper drainage and a frost-depth base addresses both.
A surcharge load is any weight resting on the soil close to the top of a wall — typically within a few feet — such as a parked vehicle, RV, boat, shed, or a fence along the top. It adds lateral pressure the wall must be designed to carry. If you plan to park, build, or store anything near a wall’s top, it has to be designed in from the start.
Each has trade-offs. Concrete block can be slightly cheaper per square foot up front, and timber is cheapest of all but rots over time. Armour stone costs more initially but typically offers the longest service life and a natural look engineered products can’t match, which is why many homeowners choose it for a build they only want to do once.
Yes — these are common conditions in Ottawa. Steep slopes and tight access do affect cost, because stone may need to be moved by hand or staged carefully, but they’re routine for an armour stone specialist. We assess access at the on-site visit so the quote reflects the real conditions.
On a steep grade, tiered walls — two or more shorter walls with a planted bench between them — are often more stable and better looking, and keeping each tier under the engineering threshold can simplify approvals. The total cost is usually higher than a single wall because each tier needs its own base and drainage, but the result is more durable.
Yes. When your wall requires a City of Ottawa permit and a P.Eng. design, we manage the application, the sealed drawings, and the inspection coordination end-to-end, so you aren’t left navigating the process on your own.
Two things matter most: building the base below the frost-affected zone, and engineering drainage so water never collects behind the face to freeze and expand. We laser-level and compact the granular base, place clear stone and geotextile behind the rising wall, and give water a path out. That’s the baseline standard for building here, not an upgrade.
Both. We assess whether a leaning or bulging wall can be partially reset or whether it needs to come down and be rebuilt on a proper drained base — and we give you an honest answer about which your wall actually needs rather than defaulting to the bigger job.
Call (613) 324-9141 or send us your details through the contact form to book an on-site assessment at no cost and no obligation. You’ll receive a written, fixed-price quote so you know exactly what your project costs before any work begins.
Whether you’re holding back a slope, replacing a failing wall, building stone steps, or framing your property with weathered-edge stone, it starts the same way: an on-site assessment and a clear, written, fixed-price quote.
(613) 324-9141On-site, at no cost and no obligation. We respond to new enquiries promptly.
A written, fixed-price quote delivered after we’ve seen the site.
Handled end-to-end where your wall requires them.
The City of Ottawa and surrounding communities, Ontario only.