FIG. J.PMaterial Guides
What Is COR-TEN Steel and How Do You Build With It?
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 what the rust does. The oxide layer forms tight and dense, bonds to the metal underneath, and then seals it. Corrosion effectively stops. The panel looks completely rusted and stays structurally sound for decades.
That patina takes somewhere between six months and two years to fully stabilise depending on your exposure. Ours came out of a decommissioned coal power plant, so it arrived stabilised already.
How much does COR-TEN steel cost in Denver?
At Revolve Reclaimed, COR-TEN panels are $3.50 per square foot with no minimum order. 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 COR-TEN panels | |
|---|---|---|
| Thickness | Thin, dents easily | Rigid, structural |
| Fastener holes | Usually full of them | None |
| Surface | Uniform, mass-produced | Unique patina per panel |
| 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, it cuts with a plasma torch or an angle grinder, and it takes a clear coat if you want to stop the patina where it is.
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.