Retort & Economiser House’s Restoration Project Report

Early 2018 saw the charity decide to restore the fabric of two buildings within the Mill’s estate, The Economiser House, and early form of heat exchanger, and the Retort House, the old gas works at the mill. The project was designed to restore the fabric of both buildings, which were in a bad state of repair at a total cost of £57,000.

The Economiser House is one of only three intact in the UK, and is believed to be the only working example left, a new glass floor is also being installed so visitors can see the pit and baffles under the Economiser with LED architectural lighting, and the internal workings are now on display through a glass inspection area which again is lit with LED lighting. The Economiser will be operated on days
when the mill is under steam, but will also be an additional exhibit for visitors generally as well as being an important part of the development of efficient energy systems that can be studied by schools.

Funding was received from 7 funders including Viridor Credits, Entrust, The Association of Industrial Archaeology, The Elmgrant Trust and The Hobson Charity, with Viridor Credits and The Association of Industrial Archaeology being the main funders.

Works to the Retort House, included resetting the louver roof tiles, rebuilding parts of exterior walls, pinning the stone walling on the north side of the building, alongside restoration of doors and windows and the installation of new guttering and drainage.

Works to the Economiser House included a new roof, repointing of the masonry, the restoration of doors and windows, the installation of a glass viewing panel and glass floor, during the course of the project it was found that the rear wall was not attached to the rest of the building and this added further costs of £550 to the project, also discovered was an amount of Asbestos which added another £650 of costs.
The Mill appointed Devon York as the main contractor and MRH MS Ltd to manage the project, further specialists James Spencer Heritage Carpenters were appointed to manage the restoration of four doors and three windows in both buildings. Volunteers carried out the installation of general lighting and LED
architectural lighting, alongside the restoration of the Economiser itself, interpretation panels are being designed in house.


Restoration Work Begins

Works have begun on the restoration of our Economiser house (earliest form of heat exchanger) and the Retort house which produced gas to light the mill and transformed working at the mill in the mid Victorian period. This allowed production to carry on beyond daylight hours. The gas retort also supplied local cottages in the hamlet of Coldharbour.

Our thanks goes to a number of donors for this project: Viridor Credits Environmental Company, The Hobson Charity, Association for Industrial Archaeology, match funding by a private donor and Viscount Amory Charitable Trust.