Energy use in a re-renovated building from 1910 - A parametric study using numerical simulations
Examensarbete för masterexamen
Structural engineering and building technology (MPSEB), MSc
During 1975-2002, 50 % of the Swedish multi-family buildings from before 1945 was renovated. A large part of these buildings are now facing a second renovation as the renovation measures are reaching the end of their service life. In order to identify further possibilities for increased energy efficiency in connection with a second renovation, a detailed investigation of the energy use has been made in one of these buildings. The thesis aims to identify the parameters that have the greatest effect on energy use in a renovated multi-family building from before 1945. The results are also generalized to be applicable on buildings similar to the studied building in order to find best measures for increased energy efficiency. Simulations with a parameter study was chosen as the method for reaching the aim. A renovated "Landshövdingehus" from 1910 was chosen as the case study for simulations. The major part of the building consists of apartments, but there are also restaurants and storage areas on the ground floor. The building was simulated in its current state but also as a 100 % residential building, the later case is referred to as the "normalised" building. The parameter study, including measures for decreased energy use, was performed on the normalised building. A comparison between the current and normalised building showed that transmission losses becomes more dominant when changing the activities from restaurants/storage to apartments. This is due to a combination of higher indoor temperatures and lower ventilation rates. A main observation from the comparison is that the activities inside the building has a large influence on the magnitude of the losses. The parameter study showed that the best measures to reduce energy use are to install a ventilation system with a heat exchanger, insulate the outer walls of the ground floor and replace old windows. General conclusions about "Landshövdingehus" are that the ground floors can account for a large use of energy compared to the other floors. Indications of energy inefficient ground floors are uninsulated brick walls and large old display windows. The ground slab is also unfavourable for the ground floor as it was not originally insulated in these type of buildings.
Materialvetenskap , Byggnadsteknik , Materials Science , Building engineering