# Insight from Review Articles of Life Cycle Assessment for Buildings
## 1 Introduction
\begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Acronym** & **Concept** & **Definition** \\ \hline \multirow{2}{*}{LCI} & Life cycle inventory analysis & Phase of life cycle assessment involving the compilation and quantification of inputs and outputs for a product/process throughout its life cycle. \\ \hline \multirow{2}{*}{LCA} & Life cycle assessment & Compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product/process throughout its life cycle. \\ \hline \multirow{2}{*}{LCCA} & Life cycle cost analysis & Analysis of financial costs for a product/process throughout its life cycle. \\ \hline \multirow{2}{*}{LCEA} & Life cycle energy analysis & Analysis of energy performance for a product/process throughout its life cycle. \\ \hline \multirow{2}{*}{LC(CO\({}_{2}\))A} & Life cycle CO\({}_{2}\) emissions analysis & Analysis of CO\({}_{2}\) emissions for a product/process throughout its life cycle. \\ \cline{2-3}  & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Definitions of LCA [2; 5; 7]. literature related to LCA-B from different perspectives. The review articles on LCA-B can be divided into the following main categories: construction materials (e.g., wood, steel, concrete) [35; 44; 45; 46; 47; 48; 49; 50; 51; 52], building types (e.g., residential buildings, office buildings, green buildings) [53; 54; 55; 56; 57; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69], building components (e.g., HVAC, heat pump, building envelope system) [61; 62; 63; 64; 65; 66; 67; 68; 69], uncertainty and sensitivity analysis [13; 16; 17; 70; 71; 72; 73], evaluation method (e.g., LCA, life cycle energy analysis (LCEA), life cycle cost analysis (LCCA), and life cycle CO\({}_{2}\) emissions analysis LC(CO\({}_{2}\))A) [5; 74; 75; 76; 77; 78; 79; 80; 81]. The concept of circular economy, exploring reuse, recycling, and design-for-disassembly, has further expanded the scope of LCA [82; 83; 84; 85; 86]. In addition, increasing studies have been conducted on the integration of digital twins, artificial intelligence (AI) and BIM in LCA-B. This integrated new technology can significantly improve the efficiency and accuracy of LCA, facilitate intelligent decision-making and help the construction industry to achieve the goal of carbon neutrality [87; 88; 89; 90; 91; 92; 93; 94]. Despite these advancements, challenges persist in data quality, technological heterogeneity, and temporal dynamics [73; 86; 95; 96]. Notably, the lack of standardized databases for regional variations remains a barrier. Based on various case studies, previous review articles of LCA-B have systematically summarized the methodologies, findings, and research directions mainly from a specific perspective (e.g., construction materials, building types, building components, uncertainty, integration of digital twins/artificial intelligence/BIM). However, few studies are observed on systematic and comprehensive investigating the current state of LCA-B that synthesize the existing review literature. Specifically, the findings and challenges summarized from the highly cited review papers are more convincing and enlightening. Therefore, the objective of this comprehensive systematic literature review is to identify the characteristic distribution of the existing review literature using bibliometric analysis and the key findings in the field of LCA-B. The organizational framework of this manuscript is systematically structured as follows--Section 2 elucidates the comprehensive research  
Figure 1: Life cycle energy framework of a building based on [76; 97]. methodology employed in conducting the systematic literature review, which comprises three sequential phases: (i) systematic data acquisition, (ii) bibliometric performance assessment, and (iii) integrated quantitative-qualitative analytical framework.