Design parameters of the timber-glass upgrade module and the existing building: Impact on the energy-efficient refurbishment process

The paper discusses the impact the timber-glass upgrade module has on energy-efficient refurbishment of multi-family buildings. The main variable design parameters of the numerical study are the height of the upgrade module and the existing building, relevant to the number of storeys, alongside with the thermal transmittance of the module envelope elements, its glazing size and orientation. The key of the study is to explore to which extent the application of the timber-glass upgrade module influences the energy need of the hybrid building regarding the aforementioned design parameters with the aim of establishing design guidelines for refurbishment with attic extension.