Sustainable domestic design

Your question is DREAM HOUSE. I suggest you visit to Zero Carbon Building in Kowloon Bay for more ideas :)

Structural:
1) Double layered walls--better insulation
2) Insulating between walls--made of recycled PET (better insulation and environmentally friendly)
3) Use locally sourced construction materials, maybe recycled ones

Architect:
1) Double layered windows--insulation, noise
2) Anti-radiation coated windows--insulation
3) Vegetation on roof / wall--insulation + absorb CO2
4) Solar water heater: use heat from sun, not electricity, to heat water
5) If possible, use "underground air-conditioning"--more energy efficient

6) Design the house with the correct SHAPE and CONTOUR according to the sun position ACROSS THE YEAR: this helps the solar panels and get maximum energy, and let in appropriate amount of sunlight into the house: not too bright/dark/hot/cold.

7) More windows: natural sunlight + heat
8) Window sills: summer sun angle is high, sun rays blocked by the window sill--house not too hot; winter sun angle low, sun rays can enter the house--warmera

Utilities
1) Solar photovoltic (i.e. solar power)
2) Induction cooking (safer, uses less energy)
3) Use appliance with Grade 1 Energy labels
4) Use ceiling fans (e.g. HVLS fans)--better ventilation, use less air-con
5) New air-conditioners can produce hot or cold air. More energy efficient than heater + standard air-con
6) LED lighting + "mood lights"--better effects, use less energy, very bright
7) Waste water recycling (e.g. from sink to toilet flushing)
8) Rainwater catchment for toilet flushing/irrigation
9) Dehumidifiers (抽濕) reduces air-con use
10) Motion sensors for lighting, air-con--better effect, reduce usage when not needed
11) Small generators e.g. bicycle machines-- for charging batteries or for radios
12) Food waste processor: reduce trash