Life cycle carbon emissions of buildings considering wood biological carbon sequestration with a piecewise linear decoration model

This study focused on three building types (steel, reinforced concrete, and timber), trying to evaluate their life cycle carbon emissions while quantifying building decoration stage carbon emissions. Besides, the three structures’ emissions at key life cycle stages were compared, revealing the potentials of timber buildings in terms of carbon reduction. The study’s contributions lie in three aspects: Firstly, a piece-wise linear model was developed for accurate decoration stage emission quantification. Secondly, a formula for building production and construction stage carbon emissions accounting for materials, height, decoration grade and area was proposed. Thirdly, a new solution was proposed to demonstrate that the carbon-negative materials exhibited positive carbon emissions after recycling. Methodologically, the study applied LCA for life cycle carbon accounting, used the developed piece-wise linear model to quantify decoration-stage emissions. It was found that carbon emissions from timber buildings typically accounted for only 30–50% reductions compared with those from steel and reinforced concrete buildings during the production and construction stage considering decoration. Across the full life cycle, timber buildings typically emitted approximately 15% less carbon than the other two types of structures. The findings offer key evidence to clarify emission differences across building structures and explore low-carbon development paths.