A building's embodied carbon is locked in the moment its materials are made — choosing timber over concrete can flip a structure from a carbon source to a carbon store.
embodied_CO2 = sum(material_i * CO2_intensity_i)
carbon-positive if sequestered > emitted
- City grid size — building plots making up the modelled skyline.
- Timber/low-carbon share — fraction of new construction using mass timber or other carbon-storing material.
- Building density — how tall/dense the buildings on each plot are, scaling total material demand.
- Retrofit rate — how fast existing high-carbon buildings are retrofitted rather than replaced.
Mass-timber towers now under construction worldwide store more carbon in their structure than was emitted building them — genuinely climate-positive construction.