It's pretty much TreeHugger policy not to show big houses in the country that are labelled sustainable, because they aren't. But that is where the clients are for architects like Altius Architecture, when they are not designing tiny green minihomes, and Graham Smith does take sustainability seriously, building in as many green features as he can, in a subtle, almost invisible manner.
The architects write:
The material palette was of particular importance as it was paramount that the building became steeped within its surroundings, and so we chose to pursue a selection of materials that would reflect the nature of adjacent landscape and in particular its seasonally changing colours and textures. True to this we incorporated the ever evolving characteristics of corten steel, the earthy tones of a deep grey/blue ‘Cape Cod’ pre-finished wood siding, as well as other products like slate and ipe wood decking.
COR-TEN is a self-weathering steel that develops a lovely rusty patina, that can cause problems if not used properly. I asked architect Graham Smith about this; he responded:
Major issues would be using incompatible fasteners and/or welding materials which can cause the Corten to fail or worse still the fastener to fail. Minor issues are electrolytic or galvanic reactions commonly between corten and aluminium, zinc, copper and stainless. For the most part these reactions can create really bad staining on one or both of the materials in contact usually the one downstream. Another common problem is that the corten will rust stain anything downstream of it including paving, masonry...
As long as you're thoughtful about how you design it, understand the basics and have an installer that knows what they're doing it is a great material with an ever changing patina and a really long service life.