A Feasibility Study on the Insulation Reinforcement Effect of the North-Facing Apartment Wall

Byeonghyeon Ryu; Hyunjae Chang

doi:10.7836/kses.2026.46.1.053

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2026 Vol.46, Issue 1 Preview Page Next Page

Research Article

A Feasibility Study on the Insulation Reinforcement Effect of the North-Facing Apartment Wall 아파트 북측 벽면의 단열 보강 효과에 대한 기초적 연구

28 February 2026. pp. 53-64

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Abstract

Korean apartment buildings are traditionally designed with a strong preference for south-facing orientations and balcony extensions are common. The south-facing façades of the dwelling units benefit from solar heat gains during winter owing to the low solar altitude at noon, resulting in relatively low heating loads. In contrast, north-facing façades do not receive direct solar radiation, which inevitably leads to greater heat losses compared with other orientations. Therefore, examining the thermal characteristics of north-facing rooms and quantitatively identifying the effects of the insulation reinforcement of north-facing walls are important for establishing energy-saving strategies for new construction and renovation projects. Accordingly, this study focused on a typical flat-type apartment unit, and the thermal environment and heat transfer during the heating period in rooms facing north were extensively investigated. Additionally, the heating energy-saving effects resulting from the insulation reinforcement of the north-facing walls were evaluated. Consequently, the north-facing room was scarcely influenced by direct solar radiation, and its average indoor temperature in winter under non-heating conditions was approximately 5℃ lower than that of the south-facing room. Although the south-facing room experienced almost no heating load, even during winter, the north-facing room exhibited heating loads of approximately 3–6 kWh/m² in January–February and December. Insulation reinforcement of north-facing walls reduced the heating load by approximately 7.2–7.9% for the entire dwelling unit, whereas a reduction of 15.8–17.2% was observed when the analysis was limited to a north-facing room. Based on these results, the insulation reinforcement of north-facing walls is expected to be highly effective in reducing the heating energy consumption.

Keywords

Energy simulation

North-facing wall

Insulation reinforcement

Heating load

키워드

에너지 시뮬레이션

북측 벽면

단열 보강

난방부하

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Information

Publisher :Korean Solar Energy Society
Publisher(Ko) :한국태양에너지학회
Journal Title :Journal of the Korean Solar Energy Society
Journal Title(Ko) :한국태양에너지학회 논문집
Volume : 46
No :1
Pages :53-64
Received Date : 2025-12-17
Revised Date : 2026-01-20
Accepted Date : 2026-02-12
DOI :https://doi.org/10.7836/kses.2026.46.1.053

Journal of the Korean Solar Energy Society ISSN:1598-6411(Print) 2508-3562(Online) 한국태양에너지학회 논문집

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