Heritage and Sustainability

Director,

It ought to be axiomatic that the most sustainable building is the one we already have, with all its embodied carbon, yet for many, old buildings present a problem. They are inadequately insulated and thus expensive to heat and, for listed buildings, the process for negotiating consents for improvements is complex, inconsistent across di erent local authorities and uncertain in outcome.

There is no firm consensus on which climate change mitigation measures are appropriate within a heritage context. Each building needs to undergo an individual consent process so that its heritage significance can be assessed, and any ‘harm’ that may be caused to this significance can be measured against the ‘public benefit’ of what is proposed.

As a result, determining what is right and wrong is open to interpretation. To inform the necessary decision process, good and clear guidance on what is acceptable is important. There is a large amount of very detailed and wellresearched guidance available from Historic England and others. But its sheer volume is overwhelming and not easy to navigate. As a consequence, many owners of historic buildings are left discouraged.

This prevents us from allowing historic buildings to do what they can do best: be flexible in reacting to changing needs so that they remain comfortable and attractive places in which to live and work. We have forgotten that buildings were adapted or “dressed” to serve the needs of their occupants, through the provision of internal wall hangings and panelling to allow a higher surface temperature and to trap warmth; externally, sun blinds were added to prevent overheating. Moreover, expectations of comfort have changed: while we naturally wear clothes outdoors to suit the season, we no longer do so indoors. The committee rooms in the Palace of Westminster itself illustrate this: a temperature of 13C is marked as “Temperate”, far cooler than would be acceptable today and made adequately comfortable by wearing heavy clothes.

Some people ask if historic buildings really matter in the context of the massive task ahead of us. Or could we just leave them as they are, avoiding all potential ‘harm’ to their heritage significance, but at the same time consigning them to diminishing use and consequential loss? If the UK wants to meet its target to be carbon neutral by 2050, historic buildings need to play their part. There are nearly half a million listed buildings and nearly 10,000 conservation areas in England alone. Upgrading all listed buildings and unlisted dwellings in conservation areas in England and Wales with a light-touch approach would result in 30% of the annual reductions in UK carbon emissions required to meet the Sixth Carbon Budget, according to figures compiled in 2021 by energy consultancy Verco. What can we do to make this happen?

In order to define the problems and suggest workable solutions, Grosvenor Britain and Ireland commissioned my practice, Donald Insall Associates, to write a policy review for them. Consultees included Peabody, Southern Housing Group, The Crown Estate, the National Trust and Historic England, supported by data from energy consultants Verco. Key recommendations to emerge included:

First, National Planning Policy which governs the historic environment should include positive policies for carbon reduction in relation to historic buildings, and ensure that these measures are seen as public benefits which can outweigh “harm” to historic significance caused by their implementation;

Second, clear guidance with positive case studies to inform and inspire should be widely available, perhaps as a supplement to the existing building regulations covering conservation of fuel and power in new construction.

Third, we should make use of existing legislation to better e ect. For listed buildings, Heritage Partnership Agreements allow owners to improve buildings without the need for repetitive consents, once an acceptable scope of works has been agreed. This would be a boon for large or complex estates.

Fourth, additional training and resources for both local authority conservation o cers and building control inspectors would enable them to guide improvements.

Lastly, and an essential measure, VAT on works to existing buildings must be equalised with that on new building to remove the disincentive to preserve and enhance our existing building stock.

These suggestions have now been shared more widely with the Ministry of Housing, Communities and Local Government, and with the heritage and architecture sector, to enable historic buildings to play their part in the addressing the climate emergency.

The full paper is available at: https:// www.grosvenor.com/Grosvenor/files/ c1/c19892d9-5734-4975-85df5d2fab87228d.pdf.

Acknowledgement: In preparing this article, I am indebted to my colleague Cordula Zeidler, from whose earlier work much of this text is drawn.