The role of hygrothermal modelling for different housing typologies by estimating indoor relative humidity, energy usage and anticipation of fuel poverty

The nature of deem-to-satisfy standards in building energy performance results in a lack of insight over their consequences. As a result, there is a huge gap between regulation and implementation in the construction industry. The procedure proposed in this article aims to implement the probabilistic approach method to design retrofitting solutions for building energetic rehabilitation and relative humidity management. This is completed by considering the uncertainty associated with a building's physical parameters, savings estimation, weather forecast, occupants' behaviour and building ventilation. A computational hygrothermal modelling approach is utilised to emphasise the differences in the indoor conditions for two typologies of residential houses common in the United Kingdom, located in three cities with different weather conditions and fuel poverty levels: Liverpool, Aberdeen, and Kent. The first model corresponds to houses built to standards from the 1920s′, with solid external walls, and the second house model uses the 2010s′ construction solution, where the double-glazed windows and the wall insulation materials are implemented. The indoor temperature is demonstrated to be efficient in the range between 16 °C - 20 °C. Lowering the current temperature set point to about 16 °C will give healthier indoor conditions regardless of dwelling, highlighting the need to review the regulation. The simulation shows that 2% heating energy can be conserved for indoor thermal comfort and extensive environmental benefits. On particular assumption of energy use per household, this work will annually contribute to the carbon footprint reduction of approximately 635.8–847 thousand tonnes