Massive Ontario limestone slabs machine-placed to create permanent retaining walls and dramatic landscape features.
Armour stone is one of the most enduring landscape materials available — and one of the most distinctly Ontario. The stone is quarried in Wiarton on the Bruce Peninsula, where 400-million-year-old limestone is split along natural beds into massive slabs ranging from 500 lbs to over 5 tons each. These stones are then trucked across the province for use as retaining walls, garden features, and erosion barriers. In the GTA, armour stone is increasingly chosen over modular block retaining wall systems for properties that want a permanent, no-maintenance solution with a natural look — once placed, armour stone walls effectively last forever, with no settling, no engineered backfill geogrid, and no cap stones to re-glue every few years. The catch is that placement requires heavy equipment: even a small armour stone wall needs a mini-excavator or skid-steer, and larger walls require full-sized excavators with thumb attachments. Site access and equipment staging often drive the project cost more than the stone itself. Buildoreno installs armour stone across Toronto, Burlington, Hamilton, Oakville, and ravine-lot properties throughout the GTA, where natural stone retaining is a superior choice for slopes that need erosion control with a landscape-grade aesthetic. We source full-weight stones (rated by ton, not by face-weight which can be deceptive), use proper machine placement to set each stone on a level base, and finish with native plantings between stones that establish over time to lock the wall into the slope.
Median project pricing in each of our busiest markets. Your exact number depends on scope, access, and site conditions — every Buildoreno quote is free, written, and itemized.
| City | Price range | Full guide |
|---|---|---|
| Toronto | $35,000–$55,000 | View → |
| Mississauga | $30,000–$48,000 | View → |
| Brampton | $8,000–$14,000 | View → |
| Vaughan | $30,000–$50,000 | View → |
| Oakville | $55,000–$90,000 | View → |
| Markham | $18,000–$30,000 | View → |
Median project pricing. See each city guide for the full small / medium / large breakdown.
We evaluate the slope, drainage, access for equipment, and aesthetic goals. We help you choose between weathered (natural face) and sawn-face armour stone, and size the stones to the wall height — taller walls need larger base stones.
We excavate the wall trench below frost line and lay a compacted granular base. For taller walls, we may include perforated drainage pipe behind the base to manage subsoil water that would otherwise undermine the wall.
Stones are placed with a mini-excavator or full excavator with thumb attachment. Each stone is leveled, set firmly against the slope, and locked against neighbouring stones. The largest stones go on the bottom course, smaller stones step up.
Granular backfill is placed behind the wall in lifts and compacted. For walls with hydrostatic load, a clear-stone drainage layer with perforated pipe is included. The backfill provides lateral support and manages water flow.
Native perennials, ground cover, and ornamental grasses are planted in pockets between stones. Over 1-2 seasons, plant roots help lock the wall into the landscape and reinforce the natural appearance.
Every Buildoreno estimate is a free, itemized written quote — no hidden line items. Your exact price depends on site conditions, materials, and scope.
See the full landscaping cost guide →Last updated: May 2026
Installed cost runs $200-$450 per ton, with the wide range driven by stone size, site access, and equipment requirements. A small garden bed border using 2-3 tons of small stones might cost $800-$1,500. A full ravine-lot retaining wall using 30-50 tons can reach $10,000-$20,000.
Face-weight stones are thinner slabs sold for veneer applications, often only 12-18 inches deep. Full-weight stones are 2-4 feet deep through their full mass and provide actual retaining capacity. Always confirm you're getting full-weight stones for retaining walls — face-weight will fail under lateral load.
Walls over 1 metre in exposed height require engineered drawings under most GTA municipal bylaws, same as modular block walls. Armour stone walls under 1 metre rarely need engineering because of the inherent mass-and-friction stability of full-weight stones. We confirm requirements with your municipality.
Yes if there's equipment access for at least a mini-excavator (about 5 feet wide). If access is too narrow for any machine, armour stone is not practical — manual placement of even small armour stones isn't safe or feasible. We assess access during the estimate visit.
Most armour stone used in the GTA comes from the Wiarton-Owen Sound region on Ontario's Bruce Peninsula, where dolostone limestone is quarried in massive natural slabs. Some armour stone also comes from Quebec granite quarries — granite is harder and more uniform but has a different aesthetic than the warm grey limestone.
Book a free on-site consult. We'll measure, talk through materials and budget, and have a plan back to you — with a value option quoted alongside the premium so you can compare.
Call (647) 254-0877