There is growing awareness of the overheating risks in new-build properties in the UK. However, this tends to be considered a problem principally for the southern regions in the UK, only becoming a serious issue in the North of England in the medium term and in the long term for Scotland. This notion tends to be largely predicated upon climate change predictions, differences in latitude and summer air temperatures. This paper describes the results from Building Performance Evaluation (BPE) studies over a two-year period from 26 occupied new-build homes across Scotland which demonstrated incidences of overheating.Results suggest that low energy buildings are susceptible to overheating despite northerly latitudes, with 54% of houses studied overheating for more than six months annually, and 27% of homes overheating for less than 10% of the year.Evidence indicated that commonly used prediction tools do not appear to adequately anticipate overheating. This paper maps common overheating causes due to design and the role of occupants, identifying the risks due to the regulatory system, prediction and procurement processes, and the design and construction.A common finding was that design and occupancy factors appear to greater impact on overheating more than location and climatic factors.

This paper describes the monitored environmental conditions in the bedrooms of 26 low energy houses in Scotland, include both naturally ventilation and houses with mechanical ventilation with heat recovery systems (MVHR). The context of the paper is the performance gap that is emerging between design predictions and actual performance of housing, and this paper focuses on the environmental performance of bedrooms. Bedrooms are of particular interest as they are the spaces in which occupants have the greatest exposure to the indoor environment, and in which conditions are relatively constant. The study indicates that ventilation is generally poor in these spaces and that both temperature and humidity frequently exceed accepted parameters for comfort and health. Increased window opening is a mitigating factor, but effects are limited by overall ventilation strategies.

Climate change and sustainability legislation in recent years has led to significant changes in construction approaches in the UK housing sector. This has resulted in the adoption of new building typologies, including the German Passivhaus (Passive House) standard. This standard aims to improve occupant comfort and energy efficiency, potentially changing the ways in which homes operate and how occupants interact with them. With increasing construction of low energy dwellings, there is an emerging gap in knowledge in relation to occupant health and wellbeing, thermal comfort, and indoor air quality (IAQ). Using data collected from a two year Building Performance Evaluation (BPE) study funded by Innovate UK, the environmental data (temperature, relative humidity and carbon dioxide concentrations) from five Certified Passive House homes in Scotland was compared. The results demonstrate problems with overheating with peak temperatures exceeding 30˝C. Imbalanced mechanical ventilation with heat recovery (MVHR) systems were identified in 80% of the dwellings and inadequate IAQ was found due to poor ventilation. Only one of the Passive Houses studied exhibited thermal conditions and IAQ which were, on the whole within Passive House parameters. This paper outlines the insights and the main issues of Scottish Passive House in the broader context of sustainability.

In recent years, thermal performance improvements have been applied to an increasing number of historic buildings towards the achievement of the legally binding Scottish carbon dioxide (CO2) emission reductions. Over 20 % of the built environment in Scotland was constructed pre 1919 and the targeting of fabric improvements in these buildings can pose a performance risk if inappropriate measures are applied. This paper discusses through a case study a Building Performance Evaluation (BPE) approach used in conjunction with the design process for refurbishment of a community owned historic building, located in Arisaig, Scotland. The community received funding to improve the energy performance of this nineteenth century stone building and committed to a 75 % reduction in CO2 emissions. BPE was conducted in 2014 as part of the design process and repeated post-refurbishment in 2015 to validate the design. The initial BPE identified high heat losses, inefficient heating and lighting systems that resulted in occupant discomfort, high running costs and consequently the loss of a community facility during the winter months. The resulting BPE quantified improvements to the building fabric, occupant comfort and reduced energy consumption, which advocated this design approach as a beneficial tool for informing historic building refurbishment.

Housing contributes significantly to greenhouse gas emissions. It is also a social determinant of health. In Scotland, 25% of households in 2019 were in fuel poverty. Current (2023) energy price increases are likely to further increase this proportion, particularly among low-income families. Fuel affordability measures implemented by the Scottish and UK Governments generally focus on achieving thermal comfort, largely disregarding appliance energy usage, termed ‘unregulated loads’. These include essential household items in kitchens such as the cooker, washing machines, fridges and freezers. The inability of occupants to afford to cook and store food and launder clothing can have broader health implications. This study reviews one year of energy consumption data collected from 17 newly constructed energy-efficient dwellings available for a combination of social rent and purchased through an affordable shared equity scheme in Scotland. The data are used to determine the proportion of total household energy consumption used in kitchen environments. Analysis indicated a vast range of 20–72% (41% mean) of total household electricity consumption was linked to the kitchen, excluding artificial lighting. In this study, energy efficiency ratings of the cookers, fridges, freezers and washing machines identified that those in social housing had the least energy-efficient kitchen appliances compared to those in purchased affordable homes. This suggests inequitable practices for kitchen appliance procurement in social homes compared with affordable homes. Overall, this study highlighted the need for larger-scale, in situ research to evaluate energy efficiency and consumption in kitchens to inform social landlords and policymakers to reduce disparities and to form a focus on fuel poverty calculations.