The U.S. has the potential to cut building emissions by 91% compared to 2005 levels, saving over $100 billion per year on energy costs. Around 28% of global carbon emissions from commercial and residential buildings come from operating them: the energy needed to heat, cool and power them; the rest from materials and construction. Three main approaches to reducing the carbon footprint of buildings are: improving energy efficiency–i.e. high-performance windows; converting services such as space and water heating to efficient, low-carbon electric sources like electric heat pumps; and technologies such as smart thermostats and connected appliances that impact how and when power is drawn from the grid.
https://buildings2050.lbl.gov/
www.anthropocenemagazine.org/2023/08/a-90-plus-percent-cut-in-u-s-building-emissions-is-possible/