R-40 insulation (plastic-foam, rockwool, pumice, strawbale/straw, cellulose,
cob, 40-80inch+ of super dry dirt)
South Facing Windows that
Radiant Floor Heating (powered by pellet/wood boiler,
CO2 Heat Pump, 5,000gallon tank filled with 190F
water heated by the summer sun, etc)
Ventilation (Bathroom vent, kitchen/stove vent, ERV for air exchange)
Dehumidifier/Humidifier (Heat Pump/AC and Evaporative Humidifier)
Vapour Barrier
Then there is the post and beams that hold up the roof, it can be 2x4 or timber or iron or alluminium or
concrete or stone or compress earth block.
Then there is the actual roof which can roof, which is usually lumber or concrete
Then there is the finish/facade (drywall-stucco-cement-stone, cob, lumber)