HUF Haus

Uncompromising Aesthetics: Famous for its stunning, transparent designs of wood and glass, German prefabricator HUF Haus maintains you can build responsibly with wood -- the process just needs a little tweaking. Windows on all sides bring the outdoors in, while efficient prefabricated thermal insulation keeps energy leaks out.

How They Do It: With no load-bearing walls, HUF interiors are wide open. While design specifics are catered to buyer preference, the components are made in the factory and assembled in a few days. Sustainably sourced materials, toxin-free paints, solar energy and rainwater recycling make HUFs nearly as earth friendly as they are easy on the eye. While they're most prevalent in Europe, you can see a HUF showhouse for yourself in Ohio, where the company has a U.S. dealer.

Cost: Starts at about $350 per square foot.