Assessing impacts of climate change on the energy and hygrothermal performance of detached houses in Sweden

Sammanfattning: Climate change is one of the most significant challenges that building sector is confronting. For example, Climate change and associated extreme events are posing a significant challenge for the building sector. Buildings should be prepared to withstand the climate changes and extreme weather that will happen in the future. Designing buildings based solely on past or average weather conditions, while neglecting the possibility of extreme weather events, is not a sustainable approach for the future. Detached houses constitute 72% of Sweden's residential buildings, but they are more sensitive to climate fluctuations than apartment buildings. Moisture and energy performances are two key aspects that helps to identify the ability of the house to holdout extreme weather. This study aims to investigate the hygrothermal and energy performance of detached houses in Sweden under current and future climate conditions, by using verified future weather data and past weather data. The investigation was conducted in three cities across Sweden: Lund in the south, Stockholm in the central region, and Luleå in the north. The reference detached houses were an illustration of detached houses from 1940s, 1965s and modern construction types. For hygrothermal and energy simulations the WUFI and Rhinoceros data tools were used, and the building modelling were based on the fact obtained from literature study. The hygrothermal results showed that all construction types were moisture safe. Despite occasional instance where the relative humidity (RH) exceeded RH critical, a thorough analysis confirmed the moisture safety of the constructions. While the energy results showed that there was a consistent behaviour of energy usage when it came to the buildings’ location. An overall observation of energy load in distinct weather scenarios (past, ECY, EWY, TDY) indicates that the decrement of heating load and increment of cooling load by time in all scenarios. The obtained result showed that the cooling demand in modern construction was higher than the elder construction types, which is caused due to their high insulation material. It is the major argument for cooling system need in Swedish buildings. Although the extreme weather conditions will never occur, still investigating these scenarios can provide building designers with a reference point for situations where climate change may cause similar conditions.