FIG. G.PMaterial Guides
What Is COR-TEN Steel and How Do You Build With It?
Written byCole Miller, Founding Partner & COO
Handles sourcing, logistics and the turf-recycling operation. Writes on materials, reclamation and moving heavy things without breaking them.
Checked by Sarah Miller · Head Honcho
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People walk into the yard, see the steel panels, and ask the same question: “Isn’t that just rusty metal?”
No. It is COR-TEN, and the difference is worth understanding before you build with it.
How does COR-TEN steel work?
COR-TEN is a weathering steel alloy — steel with copper, chromium, nickel, and phosphorus added. When ordinary steel rusts, the oxide layer is porous and flaky. Water and oxygen get through it, the metal underneath keeps corroding, and eventually the steel fails.
The alloying elements in COR-TEN change how fast that happens. The oxide layer forms tighter and denser and clings to the metal underneath, so water and oxygen have a harder time getting past it. Corrosion slows down a lot. The sheet looks completely rusted and stays sound for decades.
How much does COR-TEN steel cost in Denver?
At Revolve Reclaimed, our coal-fired steel sheets are $3.50 per square foot with no minimum order. They are exhaust port baffles out of a decommissioned coal plant, corrugated, and banded with calcium from the water that ran over them for years. Panel sizes are 26×36in, 26×42in, 32×42in and 36×36in, with roughly 400 square feet available in each dimension.
New COR-TEN from a steel supplier typically runs several times that, and comes in mill finish — you would then wait a year or two for the patina to develop.
Why not just use corrugated tin?
| Corrugated tin | Our coal-fired sheets | |
|---|---|---|
| Thickness | Thin, dents easily | Rigid, holds its own shape |
| Fastener holes | Usually full of them | None |
| Surface | Uniform, mass-produced | Unique patina per sheet |
| Weldable | Poorly | Yes |
| Price here | — | $3.50 / sq ft |
The nail holes are the practical difference. Salvaged tin has been screwed to a barn for forty years and is perforated along every batten line. These panels came off equipment housings and are clean.
What can you build with it?
Accent walls and interior cladding. Planter boxes and raised beds. Fire pits. Privacy screens and fencing. Gates. Range hood surrounds. Signage backers. House numbers. Exterior siding panels.
It welds, and it cuts with a plasma torch or an angle grinder. As above: clear-coat it if you want the colour held where it is, and expect it to keep changing if you do not.
The one mistake to avoid
Runoff stains concrete. In the first year especially, rain running off a COR-TEN panel carries rust with it, and it will leave orange streaks on a patio, a walkway, or a light stucco wall below.
This is not a defect — it is what the material does. Plan for it. Either detail a drip edge that throws water clear, set the panel over gravel or planting rather than hardscape, or decide up front that the staining is part of the look. Plenty of people do choose the last option, but choose it deliberately.
Come see it
Panels are on the rack at 800 S Jason St. No minimums, so grab one panel for a small project if that is all you need. Call 720-236-0454 to check what sizes are on hand.
Come see it in person.
800 S Jason St, Denver. Tue–Fri 10–5, Sat 10–4.