Ljudnivån på bostadsgårdar : Förbättring av den akustiska miljön för fem olika bostadsgårdar i Västerås

Sammanfattning: This thesis studies the soundscapes of five different urban courtyards in Västerås, Sweden and presents suggestions on how to improve them. Due to the increasing urbanization there is now an increased need for housing in cities, this leads to buildings that are close to both other buildings, roads and noise emitting activities. On the grounds of that there is now a higher amount of effort required to make urban courtyards a somewhat quiet and tranquil space. The need for such a courtyard is due to the negative health effects connected to a bad soundscape. Noise pollution can lead to both hearing loss and cardio-vascular diseases. The study was done by first conducting a research of the scientific literature about the subject and then making measurements and observations at the courtyards. The soundscapes of the studied courtyards ranged from annoying to pleasing and comfortable. The sound levels measured from 46 to 57 dBA, this difference of 11 dBA is perceived as about twice as loud by the human ear. To solve the issue with noise pollution we suggest a variety of solutions to the different courtyards. These mainly include noise barriers, green walls and roof, vegetation and sound masking techniques. The main conclusions are that even the best performing courtyard could be acoustically enhanced and that solutions that employ vegetation both reduce the sound level and introduce natural sounds that are pleasing to most humans.