Renewal and revival of celebrated 1970s modernist offices and gardens unveiled at Plant Basingstoke
The retrofit and regeneration of Plant, Basingstoke, formerly known as Mountbatten House and considered one of the 15 most important listed modern buildings in Britain, has been completed.
The building was originally designed in 1973 by Peter Foggo and Arup Associates Group 2 with pre-eminent garden designer, James Russell, for paper manufacturers Wiggins Teape. First christened Gateway House, the vast stepped complex comprises six levels of commercial workspace blanketed in tiered roof gardens and terraces. The gardens and building were both separately listed by English Heritage in 2015 for their design excellence and significance within British modernist architecture and horticulture.
Plant marks a major regional asset for economic development in Hampshire, offering over 19,515 square metres of category A and B multi-let office and amenity space. Client William Laxton of Mactaggart Family & Partners was instantly drawn to the scheme on account of the original Peter Foggo design fundamentals and the abundance of terracing, making it a singularly unique building.
Twelve Architects and Studio Knight Stokoe have worked closely with the client, Mactaggart Family & Partners, developer Longstock Capital, contractor, CField Construction to complete the Grant Associates and Feilden Clegg Bradley Studios design, to deliver and reinstate the buildings’ original pioneering design intent; to blend nature, wellbeing and the workplace seamlessly. In aspiring to the highest sustainability ratings across BREEAM 'Outstanding’ and WELL Platinum certifications, Plant again pioneers a new commitment to the environment and occupant that sets a remarkable standard for future commercial workplace developments.
Prominent architectural interventions include a redesigned and expanded building entrance and reception area, enhancing the arrival experience and establishing a stronger visual connection to the verdant refurbished gardens. Double-height spaces have been formed to create vertical connections between floors, increasing the sense of openness and drawing more natural light into the plan. A striking helical staircase marks an impressive, welcoming entrance area for building users.
More recent suspended ceilings and finishes have been removed to reveal Plant’s distinctive coffered slab structure and cruciform columns, preserving the building’s unique architectural character. The original curtain wall system has been carefully refurbished, improving the building’s thermal performance and ensuring its longevity. The mechanical, electrical, and plumbing systems have been fully upgraded to enhance operational efficiency and future-proof the building, contributing to its pending ‘Outstanding’ BREEAM certification.
Additional new facilities, including a cafe, gym, shower and changing rooms, secure cycle storage, and a multi-purpose function space have been incorporated to meet the needs of modern tenants.
A key driver of the project was to greatly improve access to the gardens and roof terraces, with new level access from all storeys allowing greater use and enjoyment of the much-loved and affectionately termed ‘hanging gardens of Basingstoke’. Through extensive research conducted in archives at the University of York - including Russell’s handwritten planting lists - the listed landscape has been adapted to be climate resilient and importantly, regenerative. In-depth analysis of the historic planting palettes was undertaken, replacing species poorly suited to exposed rooftop conditions, prioritising species that are better suited to their environment, and which foster biodiversity enhancements by helping pollinators and foragers to thrive.
Over 22,500 new plants have been introduced, along with 86 new trees to complement those already on the site. With no raised planters across the gardens, adapting the planting required close collaboration between the landscape architects, structural engineers, and soil specialists, ensuring even loading across the multi-level structure. The renewed planting design draws inspiration from the original design vision for the gardens; to be informal, elaborate, romantic, overflowing, and tumbling.
Much of the existing hardscaping has been restored, with every original paving element across the garden levels recorded and catalogued, temporarily removed through construction, and then replaced in-situ. A deteriorating pond has been replaced in the cloistered Level 2 courtyard with a sculpted contemporary water feature, honouring the original form of the pond, and helping to bring new sensory experience into the space. The revitalised gardens enhance biodiversity and create inclusive, engaging spaces for both occupants and visitors. Winding pathways and new seating areas invite exploration, offering opportunities for relaxation, socialisation, and quiet reflection.
A widely regarded exemplar of British modernism and commercial horticulture, Plant now begins its new life as a regional hub for growth, providing the right environment for occupants and nature to thrive.
Planning approval and listed building consent was obtained by Feilden Clegg Bradley Studios who subsequently monitored planning and listed building issues through construction. Twelve Architects completed stages 4-6 of the architectural design, including design variations under approval of conditions.
Grant Associates designed the landscape to stage 4, and obtained planning approval and listed consent in 2019, before moving to a client monitoring role through construction. Studio Knight Stokoe obtained planning and listed building consent for an amended landscape scheme in 2024, based upon the principles established in the Grant Associates design, and completed the amended detailed design.