New Marks & Spencer building will be a showcase for low-carbon design

‘The site contains three buildings of poor quality – unlisted and excluded from the surrounding conservation areas – with misaligned floor levels, cores and column grids.’ Photograph: Marks & Spencer

I write in response to Oliver Wainwright’s piece about our proposed building for Marks & Spencer on London’s Oxford Street (‘Public vandalism’: M&S wants to flatten its art deco flagship store – here are six alternative options, 7 June). As architects, we understand the benefits of retrofit, but at Oxford Street it simply isn’t feasible.

Our proposal secured support from Westminster council, the London mayor and the independent planning inspector. The highly experienced and wholly independent inquiry inspector dismissed Save Britain’s Heritage’s retrofit scheme as “so deeply problematic, even for Oxford Street, that no-one would be likely to pursue it or fund it”.