Iconic steel frame manufacturer Crittall Windows has partnered with artist Alex Chinneck to deliver A Week at the Knees, a jaw-dropping headline installation for Clerkenwell Design Week 2025.
Installed in London’s Charterhouse Square, the extraordinary 13.5-metre-long structure replicates a Georgian townhouse façade seemingly ‘sitting down’ in its own space. Crittall engineered and supplied the custom steel sash windows that bend with the sculptural form, giving the illusion of movement within a rigid envelope.
The glazing was designed to meet the demands of structural integrity while matching the exaggerated curvature of the façade. The window profiles were modelled in close collaboration with Alex’s team and Crittall CAD Technician Rachel Johnson, who adapted the company's classic steel sections to the installation’s unconventional geometry.
Russell Ager, Managing Director of Crittall Windows, commented: “Working with Alex has been an absolute pleasure. The challenge of creating something so unconventional has energised our whole team. People across the factory were excited to see the frames taking shape and to know they were contributing to such a visible and imaginative project. We’re incredibly proud to have supported a work that highlights design innovation in such a compelling way.”
The installation includes 320 metres of repurposed structural steel, and more than 7,000 hand-laid brick slips. Crittall’s contribution used high-grade recycled steel, precision-welded and finished to maintain the brand’s hallmark slim sightlines despite the bespoke curvature.
Alex Chinneck said: “My work relies on specialist collaborators. Crittall brought both technical expertise and creative openness, which made them a perfect fit. I’d be very keen to work with them again.”
Designed for public interaction, the structure is free-standing and modular, with all elements fabricated off-site and assembled in situ. The windows were delivered pre-finished to meet a compressed installation schedule.
The sculpture will remain in place until late June and is expected to tour afterwards. For those seeking inspiration in the crossover between heritage craft and structural art, A Week at the Knees is a bold example of what’s possible through design-led collaboration.
