The challenges of retrofitting older buildings

On January 9^th this year, over 180 solar panels were turned on at York Minster. They are expected to generate 70,000 kWh of energy, providing a third of the minster's electricity requirements. But retrofitting older buildings is not simply a matter of adding modern systems to aging structures. While retrofitting is often about improving energy efficiency and performance, when it comes to historic or outdated buildings, the task becomes more complex. These buildings are not just physical spaces; they are a reflection of history, culture and architectural heritage. Retrofitting such buildings requires a delicate balance between preserving their character and meeting the demands of today’s sustainability, energy efficiency, and technological advancements.

One of the primary challenges when retrofitting older buildings is getting the balance right between preservation and modernisation. Historic buildings are often protected by stringent heritage preservation regulations that aim to maintain their original architectural integrity. These regulations can restrict the types of changes that can be made to the buildings, both internally and externally. For example, needing to preserve a facade, original windows and even interior features like mouldings or fireplaces. This requires a thoughtful approach, ensuring that modern systems are integrated discreetly and do not detract from the building’s historical value.

Older buildings may also have structural limitations. Many historic structures were built with materials and construction techniques that are no longer used today. These buildings were not designed with energy conservation in mind. Single-pane windows, uninsulated walls and inefficient heating systems were common features of buildings before the rise of energy efficiency standards. Upgrading these elements, while preserving the building’s historic features can be a delicate balancing act and often involve advanced materials that replicate the original look while offering improved energy performance, which comes at a cost.

Waterproofing and moisture control present additional challenges. Many historic buildings were built with materials that are porous or less resistant to moisture, leading to potential issues like mould, mildew, and deterioration over time.

Retrofitting a historic building requires extensive planning, detailed research into the original design, and sometimes even a deeper investigation into the building’s architectural history to determine the best ways to implement modern systems while maintaining the integrity of the structure. This can result in higher costs and longer timelines compared to retrofitting more recent constructions. In some cases, this can make retrofitting less appealing from an economic standpoint, despite the long-term benefits in terms of energy efficiency and sustainability.

Despite these challenges, the retrofitting of older buildings offers immense value, both in terms of sustainability and cultural preservation. With the right approach, these historic structures can continue to thrive, blending the best of the past with the innovations of the future.