Using timber-based panels to retrofit old university buildings in Korea for carbon emission reduction: A comparative study using LCA and energy performance evaluation

Globally, the building sector is responsible for about 40% of total carbon emissions, and in Korea, this sector accounts for 24.7%. Despite various attempts to curb these emissions, they continue to rise. As part of Korea’s 2030 Nationally Determined Contribution (NDC) to reduce greenhouse gas emissions by 40% compared to 2018 levels, the building sector aims for a 32.8% reduction.

To achieve these targets, new strategies are necessary. While reconstruction and retrofitting are both potential solutions, reconstruction is energy-intensive and time-consuming due to the demolition and disposal processes. Conversely, retrofitting, which involves enhancing insulation performance and replacing old equipment with high-efficiency alternatives, offers a more sustainable option by utilizing existing structures.

Gianpiero Evola et al. analyzed the scenario of energy performance and heat transfer analysis when retrofitting old buildings with CLT panels in a pilot building in southern Italy. Bigyong Shin et al. derived an optimal plan to achieve carbon neutrality through LCA analysis when the wall was RC and CLT.

With approximately 330 universities in Korea, many having old buildings, the potential for carbon emission reduction through retrofitting is substantial. Poor insulation and inefficient equipment are major contributors to high emissions in these buildings. Enhancing insulation and upgrading to high-efficiency devices are expected to yield significant improvements in energy performance and emission reductions.

This study aims to identify the most effective strategy for reducing aging RC buildings’ heating and cooling loads. Specifically, reconstruction and retrofit using cross-laminated timber (CLT) have been selected as comparative approaches. Through Life Cycle CO₂ (LCCO₂) assessment and energy performance analysis using WUFI Plus, this research seeks to demonstrate the environmental advantages of retrofit over reconstruction. Ultimately, the goal is to provide empirical evidence that retrofit is a more sustainable alternative to reconstruction.

If the results of this study are as predicted, the carbon emissions from reconstruction are expected to be high during the LCA evaluation. Therefore, the retrofit method should be applied, and energy performance is expected to show a significant improvement compared to the previous state.