Last week we told you about the work going in Nash Staircase and what has been revealed by careful cleaning.
This week we thought we would focus on what has been happening outside to prepare the Nash Staircase and Picture Gallery for the construction work.
One of the first jobs that our contractors had to do was to protect the 1805 curved glazed roof surrounding the Picture Gallery. We already had scaffolding in the Picture Gallery to protect the visitors walking around below and to provide a crash deck in case someone fell through the roof.
The plywood surrounding the glazing is to protect the glazing and glazing bars from damage and vibration. The contractors had to work carefully in a constricted space to create this protection.
After this had been done, scaffolding was erected in the Inner Courtyard so that safe access could be gained to the roofs and materials could be brought up. This was not a simple process! The designs had to be just right, the scaffolding could not be fixed to the building at any point and no extra weight could be placed on the already fragile Picture Gallery roof and surrounding buildings.
The scaffolding is also providing a temporary roof over the Nash Staircase so we can replace the lead and remove the glass central lantern and outer protective glass for conservation.
In order to do this the scaffolding has to rest on something to give the roof stability. We are using the aluminium beams which supported the 1970s protective glazing that floats above the Picture Gallery roof.
One of the problems the architects and structural engineers had to overcome was the problem of wind loading on the building. This could make the scaffold move up to 30mm into the building which could cause structural problems. The way we have overcome this is to use wheels for the temporary roof roof to sit on. These wheels will move with the wind, reducing pressure on the building. When I first saw them I though they looked like rollerblades!
At the moment in the sunshine, the contractors are removing the 1970s glazing and putting in a new waterproof deck so measurements can be taken for steel work.
All this activity is very exciting and means that we are getting closer to our new roof! One creature is more excited than others – the property cat Chester who has taken to use the fenced area as a safe place to sunbathe!