Use of multi-layered PCM gypsums to improve fire response. Physical, thermal and mechanical characterization

• Multi-layered gypsums with PCM are physically, thermally and mechanically tested.
• A thin layer of gypsum without PCM is added to improve fire behaviour.
• Multi-layered PCM gypsums are suitable to be implemented as building inner coatings.
• Thermal properties of multi-layered PCM gypsums are notably enhanced.
• Negative behaviour against flame of paraffin wax PCM can be easily avoided.

The building sector is one of the highest energy consumers representing around 30% of total energy use. One of the recommendations of the IEA (International Energy Agency) to reduce energy consumption in buildings is to enhance the thermal performance of building envelopes. In the present study, PCM (Phase Change Material) gypsum materials have been manufactured using three different PCM inclusion methods and a thin layer of gypsum without PCM is added as external layer with the aim of improving the fire reaction behaviour. By performing a detailed physical, mechanical and thermal characterization, the suitability of the materials to be implemented in the building envelope as inner coating is demonstrated. Results show that also the thermal properties are improved in the three cases by the addition of PCM. Moreover, the negative effect of adding paraffin wax PCM into gypsum against flame can be easily reduced by the addition of a thin gypsum layer, which is a low tech and cheap solution without extra environmental impact.