In the heart of London’s Covent Garden, a 19th-century Grade II-listed townhouse has undergone a remarkable transformation. Designed by local architecture studio, Carmody Groarke, the Covent Garden Apartment seamlessly blends historic preservation with modern ingenuity, culminating in a striking new rooftop aluminum pavilion.
The success of the pavilion as a piece of architectural engineering was made possible through close collaboration with expert engineers and craftspeople and Price & Myers and Littlehampton Welding/Format.
Preserving History, Embracing Innovation
Tasked with reimagining the top two floors of a historic building originally constructed in 1877, the design team sought to enhance the functionality and spatial quality of the home while respecting stringent heritage constraints. In England, a Grade II listed building is one of special historic interest, and owners of these types of buildings need to obtain consent from local authorities for any alterations or renovations to ensure that the national, historical, and architectural interest is preserved. To achieve this, the project adopted an unconventional approach: an upside-down layout, with bedrooms housed on the lower level and an expansive open-plan living space above. New skylights punctuate the upper floor, channeling natural light deep into the interior.
At the rear of the landlocked site, the centerpiece of the renovation takes shape — the aluminum pavilion, a dramatic extension that expands the top floor to house a glazed kitchen and a sheltered rooftop terrace. The pavilion not only introduces much-needed outdoor space but also acts as a retreat from the bustling city below.
The Aluminum Pavilion: A Monolithic Statement
Unlike traditional rooftop extensions, which often attempt to blend seamlessly into their surroundings, Carmody Groarke opted for a bold architectural gesture. The pavilion is constructed using 25mm-thick solid-plate sanded aluminum, chosen for both its physical lightness and ability to create a luminous effect. The material’s distinctive qualities allow the structure to appear weightless, its monolithic sheet metal plates leaning against one another in a state of structural equilibrium.
By abstracting the form through the use of industrial materials, the pavilion achieves an elemental presence — a sculptural silhouette that stands in stark contrast to the surrounding brickwork of Covent Garden’s historic fabric.
Meticulous Detailing and Material Contrast
The refined material palette of the project heightens the interplay between old and new. Inside the pavilion, sanded stainless steel kitchen units subtly reference the metallic rooftop enclosure, while silver travertine — hand-selected from quarried Italian stone — lines the floors. The contrast between these surfaces and the warm walnut-paneled joinery in the lower levels creates a tactile experience that bridges past and present.
Crucially, the aluminum panels that form the pavilion were engineered with precision. The self-supporting structure spans 14 meters across the rear terrace, utilizing the fewest possible components. Where necessary, concealed countersunk fixings ensure structural rigidity while preserving the seamless quality of the design. All angled connections are carefully mitred, resulting in flat, precise joints that enhance the pavilion’s architectural clarity.
A Sustainable and Thoughtful Intervention
Beyond aesthetics, the project embraces the principles of circular design. The pavilion’s bolted assembly method allows for full deconstruction and recyclability, ensuring that the material remains adaptable for future use. Left raw and uncoated, the aluminum structure integrates with a timber support system, reducing its environmental impact while maintaining durability.
More than an extension, the pavilion serves as a transitional space — somewhere between interior and exterior, shelter, and openness. “It’s an in-between space where you are outside without being fully exposed,” said Carmody Groarke. Exposed to the elements yet offering protection, the pavilion creates an experience of being immersed in the outdoors while maintaining a sense of enclosure.
A New Silhouette for Covent Garden
By working closely with planners, the design team successfully navigated the challenges of preserving a Grade II-listed site while introducing a contemporary architectural intervention. The aluminum pavilion stands as a testament to how sensitive yet ambitious design can revitalize historic buildings, ensuring they remain functional and relevant in a modern context.
This transformation redefines the townhouse as a sophisticated family home, where craftsmanship, material innovation, and spatial ingenuity converge. Through a deliberate dialogue between heritage and modernity, Carmody Groarke’s pavilion has become more than an extension — it is a striking new landmark on the London skyline.