UCL Institute for Sustainable Heritage


St. Paul’s Cathedral Library Environmental Study

The Centre for Sustainable Heritage monitors environmental behaviour, using scientific methods to develop sustainable solutions for preservation and access.

The Cathedral Library in St Paul's Cathedral was fitted out in 1709 and remains largely unaltered today. It consists of historical library collections, original timber bookcases, mezzanine and wall panels and the magnificent architecture of Sir Christopher Wren. As part of a collaborative development project, an in-depth one year environmental campaign is being carried out in the Wren Library and Cathedral Triforium so that future plans to improve the environment and increase access will be based on a detailed understanding of environmental behaviour.

Monitoring is taking place intensively in the library, as well as in the spaces connected to and comparable with the library, and correlated with regularly logged visitor numbers. The data gathered will be integrated to build up a clear picture of the environmental behaviour of the library, and other spaces within the cathedral, throughout the year. Strategic mapping will provide profiles of the library environment, which will be used to inform predictions of the space's environmental performance with changes to the interpretation of the space.

These will inform plans by the Cathedral to increase the level of access to the Library and enable the Cathedral Conservation Architect to understand the effect that changes to heating and air flows within the space might have on the sensitive fabric and contents. This exemplar demonstrates how scientific research is applied in practice to develop solutions for sustainable heritage management.

Further information can be obtained by emailing May Cassar


Professor May Cassar
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This study consists of a group of interrelated 12-month environmental monitoring campaigns on temperature and relative humidity including thermal imaging, insect pests, internally and externally generated pollution, dust and light.

Simulation of visitor numbers in the St Paul's Cathedral Library is also being carried out using EnergyPlus software. 


The study has helped St.Paul's understand better the value of the heavy construction of the library which provides natural stability for environmental conditions and which in turn has led to a suitable preservation environment in recent years.

The study concluded that increased access to the library may well reduce the build up of VOCs in the library. However the potential increase in the risk from other hazards affecting the collection needs to be managed. This includes control of air exchange caused by more frequent opening of the library doors and the management of adjacent spaces as buffer zones to the external environment.

An increase in visitor numbers is likely to exceed capacity before it creates a problem for temperature and RH. The impact of person traffic on other factors, such as increases in dust, light and sources of food for pests must be managed more assiduously.