Alternatives:
HVAC: non toxic, low VOC duct materials, proper filtration and passive control
Roofing: Long lasting, natural metals.
Windows: Low VOC Sealant | Triple Pane | Low U factor
Insulation: hemp wool, sheep’s wool, air crete
Weatherstripping & Sealants: natural rubber, silicone, wool pile
Siding: reclaimed wood, recycled metal, natural stucco