The Retort House Roof

The Retort house roof is of significant architectural importance. Not only because of its age and construction but also as we believe it to be one of the only remaining ones in the county.

When Sudbury Gasworks Restoration Trust was first formed the building was in a very sorry state of repair. For many years the building had been at risk due to the dilapidated state of the roof.

With thanks to Cast Iron Welding Services, Richard Jordan, H A Briddon and all the funders that have supported the trust, we have been able to save, restore and reinstate the Retort House roof back to its former glory.

Saving The Retort House Roof

Christmas 2020 the Retort House roof started to show serous signs of decline. The Lantern / roof vent collapsed onto the main roof structure. We removed the roof tiles and added a green tarpaulin to insure the roof did not get any worse. So that we could use the tiles again we stored them within the building.

Image of sudbury gasworks before the restoration work started.
Stack of victorian roof tiles
Sudbury Gasworks building image with green tarpaulin roof

Let’s Take A Look At The Restoration Process

Today you won’t find many of the construction techniques used on the original roof. So we needed to find a team of skilled workers that specialised in heritage projects like ours. With their help we were able to safely restore the Retort house Roof, this is how.

Crane lifting the metal steel frame of the roof off.

The Removal Of The Metal Roof Structure

The 14th March 2022 saw the removal of the gas works iron work. The Cast iron trusses were lifted by crane and sent by lorry with the metal laths to CIWS for refurbishment.

A broken part of the cast iron roof

Assessment Of The Cast Iron Roof

Due to the roofs age each piece needed assessing for safety as we wanted to restore as much as possible. Some damage had occurred over the years but thanks to the trusts earlier intervention we were able to save a lot of the original iron work.

Workman assessing the brick foundations where the roof once rested.

Repairing The Roofs Foundations

Assessing the brickwork was next on the list. Removing and replacing the damaged bricks with reclaimed bricks where needed.

Cleaning, Repairing And Repainting Of The Roof Trusses

Years of neglect had seen the roof trusses become rusty and damaged. The team had to clean each one back to bare metal. They had to make repairs where needed and in some cases fabricate new parts too old. Painting of the iron trusses was next to insure it remains in good condition for future years.

Image of a piece of cast iron being welded
Cast iron roof fittings
Red painted cast iron roof trusses

The Return Of The Roof

Out with the old and in with the old, but looking little smarter. Once the iron work was back in place the team could now begin adding back the original tiles and the all important diaper pattern that once adorned the roof of the gasworks.

Image of the newly restored roof trusses and laths back in place on the roof of the gasworks
Roof Tiled being added to the gasworks roof
The completed roof of the gasworks

Lime Torching

To secure the tiles in place we used a method called Lime Torching. If you would like to find out more about lime torching you can here. To finish the roof we used Black paint on the laths and trusses. Doesn’t it look amazing?

The mixing of lime and animal hair in a large silver bin
Image of the inside of the gasworks roof showing the torched roof and black painted laths

Fun Fact!

When we first starting looking into the restoration of The Gasworks we made a little discovery.

Image of a long eared bat being held by a gloved hand

We have tenants!

The Gasworks is home to a family of Long eared bats. Currently living in temporary accommodation in the surrounding woodland. Once the building is completed we hope they will return.