Paper short abstract:

This study shows how energy modeling affects the construction process and how the professionals handles the situation when the simulation programs shows different results. This leads to discussions about what is considered as acceptable data.

Paper long abstract:

Simulating the energy use of buildings during the construction process is a way to improve the energy performance in new buildings but, as this study shows, it is a difficult task. What is defined as an acceptable outcome of an energy model depends on more than just numbers; relationships, measurability and unreliable tenants play important parts as well.

In this case study, I have followed the construction process of a small block of rental apartments built by a municipality owned housing company in the new city district Vallastaden in Linköping, Sweden. High demands are put on the energy performance of the new buildings due to the sustainability focus of the city district. To be able to meet these demands, the building company hires consultant firms to simulate the energy use of the different buildings. The different outcomes of different models and the sometimes problematic results of some models create tensions between the theoretical models and the "real world" of traditional building practices. Through observations and interviews I have studied how the professionals negotiate on which input data are the most accurate and most useful. This study provides new insights in the practical work with energy models as well as how the professionals work to resolve the insecurities in using building energy models.