Can PIR Insulation Replace Mineral Wool in Swedish Residential Buildings? : A Study of Thermal Performance, Energy Efficiency, Economic Feasibility, and Operational CO₂ Emissions

Sammanfattning

The building sector uses a lot of energy and causes large greenhouse gas emissions. Because of this, there is a growing need for more energy efficient buildings. This study examines whether polyisocyanurate (PIR) insulation can theoretically replace mineral wool in Swedish residential buildings. The study compares thermal performance, energy use, economy, and operational CO₂ emissions. The calculations were carried out in Microsoft Excel for different wall and attic constructions with mineral wool and PIR insulation. U-values, average thermal transmittance (Um), and EPpet values were calculated for Malmö, Linköping, and Skellefteå. Economic analyses were performed using the Payoff method and Net Present Value (NPV). Operational CO₂ emissions were estimated from yearly energy use. The results showed that PIR insulation gave lower U-values and lower EPpet values than mineral wool. The PIR case with extra insulation had the lowest energy use and the lowest operational CO₂ emissions. However, the energy savings were small compared to the much higher material costs. Mineral wool with extra insulation had the shortest payback period, while the PIR cases had very long payback times. The study concludes that PIR insulation can improve the energy performance of residential buildings but is not economically competitive with mineral wool under the conditions used in this study.