A-4 - Buildings A-4A - Residential Buildings¶ A-4A1 - HVAC¶ A-4A2 - Other Energy Usage¶ A-4A3 - Non-CO₂ Emissions¶ A-4B - Non-Residential Buildings¶ A-4B1 - HVAC¶ A-4B2 - Other Energy Usage¶ A-4B3 - Non-CO₂ Emissions¶ A-4C - Building Stocks¶ A-4C1 - Construction¶ A-4C2 - Maintenance and Retrofitting¶ A-4C3 - Disposal¶