Thermal upgrade works to a 19th century lodge

Over 20% of Scotland’s housing is of traditional construction, generally built before 1919. With new national energy saving targets coming into force 2019 and the need to increase energy efficiency in the domestic housing stock, there is a need for old buildings to play their part. However, when dealing with historic buildings, these is the balance to be achieved in protecting the historic fabric and character of these buildings and achieving improvements. Since 2008 Historic Environment Scotland has taken the lead in trialling and demonstrating improvements to historic and traditional buildings.

This Paper describes the repair and upgrade works carried out at Holyrood Park Lodge in Edinburgh, a protected building on the edge of a city park. The work focussed on improving the thermal performance of the building with technically appropriate and mostly natural materials that preserved the character and appearance of the listed building and minimised disruption to the original fabric. An important part of the project was also to retain or reinstate original architectural features and traditional finishes which had been lost in previous refurbishments.

Being domestic in scale and purposed by HES, it was well suited for showcasing a range of thermal upgrade measures that have been tested on previous domestic projects. Long term monitoring examined internal and external conditions and showed no substantial changes in water vapour content in the solid walls following insulation. Having two roof pitches, a warm and a cold roof were created, and comparisons made.

A building energy assessment (the EPC in the UK) was carried out before and after the works to the building. This showed that the works were effective in improving the building’s energy performance, enabling it to upgrade from Band F to Band C – a 97% improvement in energy performance without any loss of historic fabric. The journey through the EPC Assessment process also showed that with careful inputs into the assessment good results are obtained. It also showed that hasty and limited entry of information will result in a poor energy rating.

The works at Holyrood Park Lodge clearly demonstrated that a listed or protected building can be thermally upgraded to meet new energy standards, and that this can be done in a sensitive and proportionate way, which doesn’t negatively impact on the cultural significance and fabric of the building. In addition, as it is an accessible site, it has been effective in allowing people to view the measures and understand what can be done in other traditional buildings.