# Insight from Review Articles of Life Cycle Assessment for Buildings
## 3 Results
### Findings of Qualitative Analysis
#### 3.2.3 Findings from Highly Cited Papers  
Qualitative examination was further conducted based on the above highly cited review articles, aiming to facilitate the consolidation and refinement of key research issues in LCA-B. In general, the application of LCA in building can systematically assess the environmental impact throughout the entire life cycle of buildings and provide a scientific basis for sustainable building design as well as decision-making. However, its practice also faces challenges in the aspect of data, methods, and technology. The main preliminary findings and challenges/future research directions from these review articles are summarized and  
\begin{table}
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listed as shown in Table 8. The key findings and challenges/future research directions are systematically organized into the following principal categories. 1. Passive and active features are generally advocated for buildings while excessive use of these technologies may be counterproductive in the life cycle context [113]. This is mainly because the embodied carbon of high-performance materials and equipment is relatively high, and the cost of these materials and equipment are also high, low energy buildings are actually performing better from the perspective of LCA although the concept of self-sufficient buildings (e.g., net zero energy buildings) are widespread and promoted in many countries. Meanwhile, energy consumption reduction through many efficiency improvements is usually overestimated since building-users' behavior can greatly affect the building energy consumption during use phase of buildings and thus is difficult to predict. Therefore, further investigation is required to identify their differences. \begin{table}
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**Key Findings** & **Challenges/Future Research Directions** \\ \hline
2009–2015 & \\  • Excessive use of passive/active features in buildings can be counterproductive.  • Low-energy buildings outperform self-sufficient (zero operating energy) buildings in life cycle assessments (LCAs).  • Embodied energy becomes more significant as buildings become energy efficient.  • Lack of accurate data and standardized methodologies hinders research.  • Inhabitant behavior is unpredictable, limiting LCA practicality.  • Case studies are difficult to compare due to varying properties (building type, climate, regulations, etc.).  • Urban areas dominate research, with rural areas underrepresented.  • The use-phase of buildings contributes the most to environmental impacts. & \\ \hline
2016–2019 & \\  • Predabricated structures tend to exhibit superior long-term sustainability metrics when assessed across entire life cycle phases.  • LCA, LCC, and social life cycle assessment (SLCA) can be systematically integrated within a life cycle sustainability assessment model (LCSA).  • When LCA is applied across the entire building scale, decisions based on isolated LCA of materials or components may lead to incorrect conclusions.  • 3D printing and modular construction show promise for sustainability.  • Integration of IBM-LCA simplifies early-stage design decisions.  • Most LCAs focus on energy refurbishment, neglecting structural repairs.  • Carbon footprint studies often yield inconsistent results. & \\ \hline
2020–2025 & \\  • Levelized cost of energy decreases with storage duration.  • BMI integration with LCA improves design accuracy but faces interoperability challenges.  • 3D printing concrete technology offers material flexibility and cost savings.  • Key challenges for green construction: higher costs, longer timelines, poor staff coordination/awareness, data gaps, and inadequate policies.  • Construction phase accounts for 20–50\% of total  • carbon emissions.  • Few studies clarify how green roofs and walls improve quality of life, biodiversity, esthetics, environmental health, and recreational opportunities. & \\ \hline \hline \end{tabular}
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