Gulassa & Company has been in business since 1990 in Seattle providing comprehensive design and fabrication. They work out of a shop in Queen Anne – but don’t knock on their door thinking it’s a showroom – it’s a production facility. Contact your interior designer to see their work in person. This description is from their website: “We are wood workers, metal workers, glass artists, upholsterers, architectural and graphic designers. By collaborating with clients, architects, contractors, and designers, Gulassa & Company is able to successfully resolve the most complex design issues.”
Here are a few of my favorite pieces from their website.

Japanese Stool. Handcrafted from blackened and oxidized steel using an English Wheel

Stitched Table. Bog Oak and blackened steel

Sculpture Base: Short, Blow-Down Oxidized Douglas Fir & Blackened Steel. Also available in Tall, Olive Ceruse Oak & Blackened Steel. A special sculpture or object would look amazing on one of these bases.

Steel Flooring. Each piece is 24″ x 24″ and has 4 countersunk holes w/screws. I’d imagine you could use this system for walls as well. Check that with your architect.
Be sure to visit the custom work section to see more from the talented artisans at Gulassa. It’s clear that Seattle Architects/Clients enjoy collaborating with them to produce unique details.