Historic Churches 2020

BCD SPECIAL REPORT ON HISTORIC CHURCHES 27 TH ANNUAL EDITION 7 Liturgically, the design at Liverpool was also innovative and experimental, an outstanding monument to the Second Vatican Council. The interior of the cathedral is dominated by the unbroken space of the large circular nave around which the chapels are arranged, and which is dominated by its crowning glory – the lantern. The lantern contains one of the largest stained glass windows in the world and is constructed in ‘dalle de verre’ glass (see glossary) by John Piper and Patrick Reyntiens. At Liverpool, the lantern is the crowning glory, with Gibberd carrying through the belief that cathedrals, metaphorically and symbolically are the crown of the cities they inhabit. Unfortunately, there have been inherent problems with the structure since its construction in the 1960s, as many of the techniques and materials used were untested and have not performed well over time. Soon after opening, the cathedral began to exhibit architectural flaws, the most serious being substantial leaks through the aluminium roofs, failure of the mosaic cladding panels which encase the concrete frame externally, and water ingress through the lantern, which periodically splashed into the sanctuary below. Problems continued throughout the 20th century and into the 21st, made worse by a lack of agreed approach to the defects, which remained poorly understood. Ad hoc and experimental repairs were trialled without adequate recording or monitoring, which prevented lessons being learned when attempted repairs subsequently failed. Unrecorded repair efforts to the lantern that have been identified include overpainted glass fibre strips to exterior joints, a silicone wash and aluminium flashings. All of these attempts have not only negatively impacted the functioning of the lantern, but have also had a substantial impact on its visual appearance. A major survey was carried out in the 1980s and unsuccessful repairs were made in the 1990s and 2000s. By 2014, water ingress through the lantern has reached such intensity that all agreed a new, radical approach was needed. Purcell architects began work with the cathedral to address the unique conservation challenge it presented. Before recommendations for repair could be made, it was vital to fully understand the lantern through an assessment of its construction techniques, its current condition, its environment, its significance and the original design intent. In 2016, Liverpool Metropolitan Cathedral had been awarded research funding from the Getty Foundation as part of the Keeping it Modern initiative, and this now enabled the architects to prepare a detailed conservation management plan. CONSERVATION MANAGEMENT PLANNING Conservation management planning is a vital instrument in any toolkit for managing change in an informed way, and can be broken down into three steps: Step 1 Gain an understanding of significance through an assessment and articulation of what makes a place special Step 2 Identify ways in which this significance is vulnerable but also where it might be enhanced Step 3 Transform these issues and opportunities into repair principles and practical policies which inform and manage change. Step 1: Understanding significance At Liverpool Metropolitan Cathedral the conservation management plan supported the architectural team to make appropriate decisions and avoid the mistakes of the past by giving them a better understanding of significance and the underlying causes of deterioration. Detailed historic research was carried out in the cathedral and Gibberd archives to understand how the concept design had developed into Inherent flaws in the matrix of the stained glass lantern caused water ingress inside the cathedral.