SWA Member Shines In County Hall Window Restoration

The Steel Window Association (SWA) represents the UK’s foremost specialists in the preservation and refurbishment of steel windows and doors – particularly within listed buildings, heritage properties, and conservation areas. Among its expert members is Associated Steel Window Services (ASWS), an architectural heritage refurbishment specialist which has completed the restoration of 40 distinctive ‘porthole’ and rectangular steel windows at County Hall overlooking Westminster Bridge.

The project comprised the 5^th and 6^th floors of The Marriott Hotel, part of the iconic County Hall building which first opened in 1922, where ASWS has undertaken multiple contracts for different clients over the past 30 years. This most recent one was won partly on the basis of its unrivalled experience in the field, but was the first time the company had worked with either the main contractor Red Construction or Studio Loren, which led the design work.

Having initially assisted a previous architect with technical advice and preliminary assessments of the damage the ageing steel windows had suffered. Steel‑framed windows are a hallmark of many heritage buildings, and unlike modern alternatives, they can be refurbished repeatedly over decades, preserving both character and longevity. ASWS began work on site during the summer of 2023 but had to take multiple breaks due to the complexity of the internal reconfigurations. 

Significantly, the difficulty of overhauling and redecorating the 15 crescent-shaped porthole windows at 5^th floor level, that included a large central roundel with no opening vents, and the two dozen rectangular windows, mainly measuring 1800 x 2000mm and arranged across both floors, was magnified by it not being possible to scaffold the elevations involved.

The Operations Director for ASWS, Kris Bennell, explained: “While we were only decorating the inside of the windows, a lot of them had to be deglazed which, without scaffolding, required special measures and very strict procedures to ensure the work was carried out safely - both for our staff and the public. Not only was it many of the steel frames with their through-glazing bars that were in need of significant repair, but much of the glazing also had to be replaced, while all of the ironmongery had to be demounted. The glass was internally beaded which helped, but being located up on the fifth floor there is obviously a large potential ‘fall zone’ so we had to set up quite a wide exclusion zone on the ground below; while we worked during County Hall’s non-operational hours.”

While the majority of the windows were refurbished in-situ, two which had been isolated for decades by a false wall were found to be heavily corroded as they took the brunt of the weather off the river. Fortunately, these were demounted from a balcony and removed from site for full restoration: with shot-blasting revealing many parts that required replacement.

Where the original hardware could not be saved, SWA member Steel Window Fittings provided B205 non-locking window handles; chosen for the traditional design. To improve upon the original, these handles were fitted with connecting rods as part of a duplex system to maintain a heritage appearance. To enhance security, B59 knobbed slide stays were also fitted, offering the flexibility to set the width of the window opening. A custom RAL finish was chosen to contrast gently against black frames.

The SWA offers UK wide coverage with member companies able to carry out the full range of contracts from the repair and restoration of heritage windows through to the installation of major fenestration packages in contemporary commercial, residential and other types of developments. For further information on the Steel Window Association or if you’re interested in becoming a member, please visit www.steel-window-association.co.uk