Buttress Architects | Wentworth Castle Glasshouse

When we were appointed to the Wentworth Castle and Stainborough Park Heritage Trust the glasshouse was badly corroded, missing the majority of the original glazing and overgrown by Rhododendron.

On the Buildings at Risk Register, the entire frame was supported by a temporary steel structure and access for the condition survey was undertaken in Kevlar suits to protect from the risk of falling glass.

The trust had actively been seeking to secure the glasshouse’s future for ten years since narrowly missing out on winning the TV series restoration; finally gaining the backing of the HLF and EH.
Components of the frame were repaired and replaced as per the engineers’ report. Where the frame was replaced we took casts of the original and created new molds. Where possible we have specified higher performing contemporary elements for the glasshouse, combating the issues that caused significant damage whilst retaining the integrity of the structure. For example, the main structural columns had integral rainwater down pipes.

Working with a specialist manufacturer we specified ductile iron to be used for the frame as it remains close to the original cast iron but is less susceptible to erosion.
Our project brief was to conserve where possible, and restore the glasshouse; designing a new extension to act as visitor gateway to the grade I listed parkland. Initial archival research and review from the structural engineers identified how much of the structure could be restored and what needed to be replaced. After the remaining glazing was removed, the entire structure was labelled, dismantled and taken off site to a controlled environment.
On the columns, we designed access panels to the internal down pipes to allow for maintenance and lined them with bitumen paint. We also created new spitters to sit on the perimeter gutters and, taking precedent from archival research, designed the new crested ridge piece which had been lost from the original.
All glazing had to match the thin profile of the original agricultural glass whilst being strong enough for snow loads, and to allow public use of the restored building. A specialist hand drawn glass was specified that matched the specifications whilst retaining the visual imperfections of the original glazing.
A new extension has been designed, sitting on the footprint of the original potting shed, and providing facilities that allow flexible use of the glasshouse for events and education groups. Working with URS on the landscape proposals, the glasshouse has a dedicated terrace with open vistas across the listed parkland so integrating the building to the wider ‘World at Wentworth’ visitor attraction.
Civic Trust Conservation Award 2015: Winner
National Lottery Awards 2011: Shortlisted