“Coreten” is a weathering, meaning rusting, corrugated roofing/siding product. We are considering using this as an accent roof on a small cantilevered part of our house. I understand that it can stain concrete until the oxidation process stabilizes. I was wondering if it will also stain siding even if there is a finish on the siding. Anyone have any experience using this product and can tell me how much staining there actually is?
http://www.flatironsteel.com/coreten.html
Thanks
Old masonry may look tough, but the wrong mortar can destroy it—here's how to choose the right mix for lasting repairs.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
I have seen several corten bridges and high voltrage towers, and even one building (the US Steel building in Garland Tx), but I can't imagine a residential use for it.
"Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
My impression (no direct experience) is that it will likely stain just about any material. The way to deal with it is to confine the runoff to a vertical channel under the member, so that the surface of the channel will stain more or less uniformly.
Unlike FastEddie, though, I think it would fit in well in certain types of residential construction. Probably not a good fit for a classic colonial, though.
Well, coming from the "Steel City", I look at Corten steel every day. The largest building in town is built from 64 floors of it. FWIW, the building was put up in the 60's I think. It still stains everything around it some 40 years later. They installed brown sidewalks around the building to minimize the effect. That said, if your roofing is staining your siding, you've got problems other than your choice of roofing materials. Staining will occur where runoff flows off the roof and onto some other surface, but your roof runoff should not be hitting your siding.
Mike Hennessy
Pittsburgh, PA
View Image
In Michigan they built lots of the buildings for the School of Architecture at U of M out of Coreten. Sidewalks are all rusty looking. Looks like an abandoned mill or junkyard.
Michian DOT also required bridges to be built of it before they found out that it NEVER stops oxidizing! And this is accelerated by use of salt in winter. OOPS. After a few things rusted through, they changed the law, IIRC.
I wouldn't use it, at least not where there is rain or salt! Maybe in Arizona. Look good in a desert!
"In Michigan they built lots of the buildings for the School of Architecture at U of M out of Coreten. Sidewalks are all rusty looking. Looks like an abandoned mill or junkyard."You must be thinking of a different building/buildings. There is only one architecture building at U of M and it's built of mostly brick and glass like the majority of UM buildings. It's not built of coreten. It IS poorly built and in need of more maintanence than given and some of the structure is leaking rust. In accordance with the tradition of college architecture buildings, it is currently considered one of the ugliest/poorest designed buildings on campus. It is going to be added to and remodeled soon, supposedly in a very "sustainable" way. From my designer standpoint, I think coreten is a great look for either houses an commercial structures, yet from my builder standpoint, I feel like I work to prevent materials from rusting or otherwise oxidising and degrading.gk
IBM had the "Rust Bucket" in Bethesda MD, a Corten building. They had to be real careful that all the water drained away from sidewalks or they would have been brown. This thing was bleeding rust years after they built it. I suppose it still is.
I installed it on John Nasbitt's home inn Telluride, CO, where the intent of the architects was to blend to the mining town atmosphere, where the old mills and sluices were tinned over in corrugated rooofing.
I tend to think that it will stain ontinually, though I can't imagine why that is a concern for siding. The material should overhang enoughthat water does not spill down the siding. If it does, there is something else wrong with the design or installation.
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
It's not used as much as it used to be. But wherever it's used for aesthetic reasons, it's usually someplace prominent (i.e., exterior sculptures, vertical surfaces, etc.). Not so much on roofs.
It's more expensive, sometimes hard to get, and will stain.
View Image
View Image
Edited 9/3/2008 1:36 pm ET by shtrum
Edited 9/3/2008 1:47 pm ET by shtrum
Not any personal experience but this house in upstate NY has always fascinated me. I know there was some issues with the coreten paneling on the Arts Tower at Carleton University in Ottawa, might want to search that out.
http://www.archphoto.com/T.html
It should be noted that there is "Corten" and "Coreten", apparently two different products. I suspect that the patent on Corten ran out, allowing other manufacturers into the field. (A little surprised that "Coreten" isn't a trademark infringement, though.)The two products appear to be fundamentally identical, although it's hard to say for sure.
In science it often happens that scientists say, "You know that's a really good argument; my position is mistaken," and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. --Carl Sagan
I have a shipping container, aka conex box, aka seatrain.
They are used all over for storage especially on big jobs everybody and his brother in law will have one. I have noticed a sticker several times over the years that say "repair only with corten steel".
I don't know if I have the spelling correct or not, I wonder if it is the same stuff and if there is any reason why different steels shouldn't be used in the repairs/what kind of dissimilar metal reactions are occuring?
Dan,
COR-TEN¯ was developed by United States Steel and they still hold the trademark to it.
It's interesting to note that USS hasn't recommended COR-TEN for architectural applications, (roofing, siding, etc) for over 20 years for a number of reasons.
http://www.ussconstruction.com/metal/metal/corten.shtml
They both appear to be weathering steels. Makes you wonder why one is recommended for roofing, and the other isn't.
Possibly the second manufacturer is willing to fill the requests for the oxidizing steel for architectural use that USS has abandoned.
I know there is a market for it and that USS quit pushing it or selling into that market.
They can't get your Goat if you don't tell them where it is hidden.
The only difference between Co-Ten and regular steel is that the rust doesn't flake off, allowing the rust to continue through the steel. That's all.
Until that base layer forms, the stuff will stain materials around it just like any other rusting steel.
With Cor-Ten oxide layer (rust) is more tightly bound than with regular steel. This is not simply "not flaking off", but in addition forming a barrier against further oxidation. Silver and copper similarly form a "tight" oxide barrier that prevents further oxidation (and they do it somewhat better than Cor-Ten).IIRC, the problem with iron and regular steel is that the oxidized material is larger (more volume) than the non-oxidized material, causing the flaking we associate with regular rust. The oxides of most other common metals don't have this problem -- they don't expand as they "rust".Somehow the combination of copper and other elements in Cor-Ten (and Coreten) creates an alloy that doesn't expand (much) as it oxidizes.
In science it often happens that scientists say, "You know that's a really good argument; my position is mistaken," and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. --Carl Sagan