Understanding historic building services

Richard Stocking
When I, as a conservation practitioner, consider building services in relation our nations historic and architecturally important buildings, it is most likely to be about reconciling the requirements of an owner wanting to install hi-tech solutions, with the needs of an historic building.

I, my colleagues and countless other conservation professionals are frequently faced with the challenges created by building services engineers and designers unacquainted and unaware of the importance and significance of the buildings in which they work, however well-intentioned they may be. We try to strike a balance between the needs of the building, the occupants and arguably the global environment.

Whilst our attention, when deliberating building services is perhaps dominated by the new, what about the value, importance and history of historic building services? How have mechanical and electrical services that we have come to rely on so intimately, such as air conditioning, evolved and developed within our buildings?

These were some of the questions I needed to grapple with when posed with an unusual opportunity to investigate an historic ventilation system located within the roof void of an impressive Grade I listed building in the historic English town of Warwick. The current building was constructed in the middle of the 18th Century dramatically remodelling and integrating aspects of an earlier 17th Century building.

When I accessed the roof void for the first time and was shown the surviving parts of the system, it was one of those occasions where recognition and understanding of what you are presented may not be immediate, but where instinct combined with specific observations tells you that you are looking at something so very special.

Survival of historic ventilation systems as found in the Warwick building are very rare; its survival being fortuitous rather than planned. Proposed works at this building would potentially have necessitated the loss of important surviving elements of the ventilation system, an unfortunate and unquestioned fate all too common with historic services. SNC Lavalin’s Faithful+Gould business were appointed to assess and understand the potential impact of the proposals. Had we not challenged the proposals and identified the arguably ‘national’ significance of the surviving system, its fate alarmingly may have been very different.

I was fortunate to obtain the specialist input and advice from the current Chairperson of the Chartered Institution of Building Services Engineers (CIBSE) Heritage Group and Senior Building Services Engineer at Historic England, Andrew More.

It was after our joint inspection of the surviving fabric that the importance and significance truly became apparent. With Andrew More’s years of experience, this was only the second system with timber ducting that he had observed. Guillotine style sliding timber doors survive and would have provided a degree of control over air movement within the ducts. These were operated by a rope and pulley system with the wall mounted pullies still present. The electric fans added to the system in the early 20th Century, to assist with the drawing of air through the duct work are also an extremely rare and unusual survival.   

The history of artificial ventilation is inextricably linked with a dramatic increase in medical knowledge during the 19th Century and in response to the unhealthy living conditions, predominantly within cities. Indeed, reformers like Florence Nightingale emphasised and promoted the importance of outstanding ventilation which led to hospitals being built with large windows and fireplaces. Artificial forced ventilation was developed in parallel with the advances in central heating. Some early 19th Century systems used heat passing through a masonry duct near the centre of a building to stimulate airflow. This is the type of system found within the example building at Warwick.

The Warwick ventilation system has tremendous evidential and historic value, clearly recording in one system the influential technological developments that were made during the mid-19th to early 20th Century in artificial ventilation.

Any subsequent proposals that may impact the historic ventilation system within this building can now be assessed with a far clearer understanding of the importance and significance of this rare survival. The importance of this historic system meant that proposals could not be justified, however it is not always as clear cut. We have a need to ensure that our heritage assets have a sustainable future and we need to consider how best to service these in ways that are harmonious with their conservation. This could necessitate change and it is how we manage this change that is so very important to impart.

Fundamental conservation principles adopted when working with important historic fabric should also be applied to historic services. Understanding what you are working on is crucial, as is minimising intervention, avoiding any unnecessary damage and creating solutions and changes that where ever possible are reversible. 

This example demonstrates the importance that understanding what you are trying to repair or adapt, has on minimising potential harm by inappropriate intervention. Understanding how historic services work together with their inherent sophistication and interest are vitally important to informing future decisions. Some historic services have the potential to be reused such as heat emitters and lighting equipment and can add considerable character to buildings. Ideally historic services should remain in active use for as long as is practically possible and safe to do so. Where services form an important part of the historic, evidential and aesthetic value of a building every effort should be made to retain important services in situ, as evidence of how a building was once serviced. 

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