## 3 Materials and Methods
### Model of Accounting for Carbon Footprint in the Materialization Stage of Prefabricated Housing
#### 3.3.1 Construction of an Indicator System for Impact Factors
\begin{table}
\begin{tabular}{p{128.0 pt} p{128.0 pt} p{128.0 pt}} \hline \hline
**Dimension of Analysis** & **Factors** & **Explanation** \\ \hline \multirow{8}{*}{The building material production stage} & Material selection and production S\({}_{1}\) & Different building materials have different carbon footprints. Choosing materials with a lower carbon footprint, such as recycled materials or low-carbon concrete, can reduce a building’s carbon footprint. & \\  & Waste disposal S\({}_{2}\) & Waste materials generated during production and construction need to be disposed of. Proper waste management can reduce adverse environmental impacts, including carbon emissions. & \\  & Equipment efficiency S\({}_{3}\) & The energy efficiency and effectiveness of equipment used in the production and processing of building materials affect carbon emissions. & \\  & Energy consumption of raw materials S\({}_{4}\) & The production and processing of construction raw materials requires energy, including electricity and fuel. The use of electricity from renewable sources and production processes that optimize energy consumption can reduce energy-related carbon emissions. & \\ \hline \multirow{8}{*}{Conveyance building materials phase} & Transportation tool selection S\({}_{5}\) & Different types of transportation generate different levels of carbon emissions. Choosing low-carbon means of transportation, such as electric vehicles and efficient trucks, can reduce carbon emissions during transportation. & \\  & Type of transportation energy S\({}_{6}\) & The use of different types of fuels or energy sources can also affect carbon emissions. Choosing to use renewable energy or low-carbon fuels can reduce carbon emissions during transportation. & \\  & Transportation distance S\({}_{7}\) & Longer transportation distances lead to more fuel consumption and carbon emissions. Optimizing the supply chain, choosing manufacturers close to construction sites, and reducing transport distances can reduce carbon emissions. & \\ \hline \multirow{8}{*}{Component manufacturing phase} & Component production process S\({}_{8}\) & Different production processes can have an impact on carbon emissions. Some production processes may require high temperatures or chemical treatments, which can lead to higher carbon emissions. & \\  & Waste and wastewater treatment S\({}_{9}\) & The production of prefabricated components may generate waste materials and wastewater, and additional carbon emissions may be generated during the treatment and disposal of these wastes. & \\  & Production size and volume S\({}_{10}\) & Large-scale production may be more efficient than small-scale production, and appropriate mass production can reduce carbon emissions per component. & \\ \hline \multirow{8}{*}{Components’ phase of transportation Losses during transportation S\({}_{13}\)} & Packaging and containers for precast components also affect carbon emissions. Excessive packaging increases energy consumption and waste generation, and choosing lightweight packaging materials can reduce carbon emissions. & \\  & Efficiency of component transportation S\({}_{12}\) & The efficiency of transportation has a direct impact on carbon emissions. & \\  & Losses during transportation S\({}_{13}\) & During transportation, building materials may be subject to wear and tear due to shocks and vibrations. This may result in the need for additional production and transportation, thus increasing carbon emissions. & \\  & Emissions from transportation are also an important factor. For example, the emission standards and technical status of trucks and transport vehicles affect the level of carbon emissions. & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Indicator system for the elements that affect the prefabricated home industry’s ability to materialize its carbon footprint.