National Audit Office installs Steel Windows

National Audit Office installs Steel Windows

West Leigh were delighted to be a part of a major refurbishment programme carried out by Wates Construction on the National Audit Office in London, which has featured the installation of nearly 700 W20 and W40 windows doors and screens.


West Leigh employed W20 and W40 sections to fabricate new frames for all the openings in the prominent property. T P Bennett and HOK International were the architectural practices providing for this very demanding project.



One of the architects involved with the project for HOK, Jean Letherby, recounts: “The NAO offices were originally built for Imperial Airways in 1939, and very much reflected the Art Deco style of the times. The two wings were added in the sixties. W20 steel windows were therefore used for the refurbishment of the older structure, while W40 were considered appropriate for the other two elements. This was a large and particularly challenging project and West Leigh performed well on it.”


The W20 windows were produced with both horizontal and vertical pivots, as well as bottom hung vents and side hung casements which exactly matched the existing the Grade II listed building. The W20 sections were also employed to produce some automatically opening smoke vents. The 16 mm IG units contain two leaves of toughened clear float glass with a krypton filled cavity.



As the two ‘wings’ of the building are not listed the architect had free range as to what to put to the planners and chose a rather dramatic large pane fixed frame option with reflective spandrel panels to mask the structural concrete columns. There were two staircases that had electrically powered actuators linked to the building’s fire alarm system to allow smoke release in the event of fire.


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