I am designing a home for Habitat for Humanity in a mixed-humid climate. I am trying to find great green products to use while keeping our construction cost to under $35,000. Specifically, I am trying to find some good windows and carpeting, but any other material recommendations would be welcome. So far we are looking at CMU block foundation (with a sealed crawlspace), TJI floor joists, 2×6 smart framing, attic roof trusses (fully insulated attic with mechanicals inside the envelope), cement-board cladding over rigid insulation, exposed-fastener galvalume metal panel roofing, recessed cfl cans, and an air-source heat pump. Thanks!