Innovative Facade Strategies for Energy Efficiency in Educational Buildings: A Case Study of Hassan Najjar School, Iraq
DOI:
https://doi.org/10.38027/jsalutogenic_vol5no1_10Keywords:
Phase Change Materials, Thermal Insulation, Building Energy Simulation, Educational Buildings, Hot‑Arid Climate, Thermal Comfort, Synergy, RetrofitAbstract
Educational buildings in hot‑arid climates endure severe thermal stress that compromises both energy performance and occupant wellbeing. This study presents a simulation‑based assessment of innovative facade retrofit strategies for Hassan Najjar School in Erbil, Kurdistan Region, Iraq. Four scenarios were modelled with DesignBuilder v7.3 / EnergyPlus: (a) the uninsulated baseline, (b) Phase Change Material (PCM) only, (c) high‑performance phenolic foam insulation only, and (d) a combined PCM‑insulation assembly. The combined strategy reduced the whole‑wall U‑value from 1.529 W/m²·K to 0.186 W/m²·K (an 87.8 % decrease) and lowered annual energy consumption by 28 % (11 900 kWh/year). Importantly, the energy saving surpassed the arithmetic sum of the individual PCM and insulation savings, demonstrating a synergistic effect. Thermal comfort improved substantially, with the Predicted Percentage Dissatisfied (PPD) falling from 73 % to 18 %. Model validation against 2023‑2024 utility records yielded a CV(RMSE) of 7.8 % and an NMBE of 2.1 %, within ASHRAE Guideline 14 limits. Sensitivity analysis identified PCM melting point as the most influential parameter. Economic life‑cycle analysis shows a payback of 8.8 years and a 50‑year net present value of approximately $85 000. The findings establish a replicable, evidence‑based framework that connects building performance simulation to actual funding acquisition, demonstrating how salutogenic‑driven facade retrofits can transform educational environments in harsh climates.
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Copyright (c) 2026 Saya Faruq Laeq, Omar Hamad Farag Al-Gburi (Author)
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