Hartfield Road, Wimbledon: Commercial Retrofit and Vertical Extension

Client: Wimbledon Investment Property Limited

Architects: dMFK Architects

Description of Development: Demolition of existing roof extension and erection of part two-storey and part three-storey extensions at roof level to provide additional Class E commercial floorspace; comprehensive façade refurbishment; provision of external terraces; new cycle parking and end-of-trip facilities; sustainability and urban greening enhancements

Location: 41–47 Hartfield Road, Wimbledon, SW19 3RQ

Project Overview: Retrofit-Led Commercial Intensification in Wimbledon Town Centre

The Hartfield Road project delivers a design-led retrofit and vertical extension of an existing commercial building within Wimbledon Town Centre, optimising the site to provide high-quality, future-proofed office accommodation in a highly accessible location.

Situated within the designated Town Centre, Tall Buildings Zone and London Plan Opportunity Area, the scheme responds directly to strategic policy support for intensification and commercial growth in well-connected centres. The proposals transform an underperforming postmodern office building into a contemporary, energy-efficient workspace, delivering a net uplift of 1,164sqm of Category A commercial floorspace (increasing total GIA to 4,088sqm).

Maddox Planning acted as planning consultant throughout the project, advising on planning strategy, leading pre-application engagement, coordinating the multidisciplinary consultant team and preparing the full planning application and supporting documentation.

Key Issues Addressed

Principle of Development and Town Centre Growth: The site lies within Wimbledon Town Centre and benefits from a very high level of public transport accessibility (PTAL 6a). National, London Plan and Local Plan policy strongly support the retention, refurbishment and intensification of employment floorspace in such locations. The scheme delivers a substantial uplift in high-quality office accommodation, supporting economic growth, job creation and the continued vitality of Wimbledon as a major centre. By refurbishing and extending an existing commercial building rather than redeveloping the site, the proposals make efficient use of land in accordance with the NPPF and London Plan objectives.

Design, Scale and Townscape Integration: Hartfield Road has undergone significant transformation in recent years, with taller commercial buildings establishing a clear urban scale. The proposals remove the existing roof extension and introduce a part six and part seven storey building (c.27.1m at its tallest), remaining below the height of nearby landmark buildings such as the Travelodge and Kindred House. The additional storeys are carefully set back at upper levels to mediate between the taller commercial frontage and lower-rise residential properties to the rear. The top storey is expressed in a lighter tone to create a visually recessive crown, while existing architectural features are extended upward to reinforce the building’s corner prominence. The façade refurbishment rationalises dated glazing and detailing, significantly enhancing the building’s contribution to the street scene and activating the ground-floor entrance. Pre-application feedback confirmed support for the proposed height, massing and architectural approach.

Quality of Accommodation and Workplace Provision: The scheme reconfigures and upgrades the existing internal layout to provide flexible, subdivisible commercial units from ground to sixth floor levels. Two lift cores and stair cores are retained, improving efficiency while minimising structural intervention. New landscaped terraces at fifth and sixth floor levels provide high-quality breakout space, replacing and enhancing the existing fourth-floor terrace. Regulation-compliant sanitary provision, shower facilities, lockers and improved servicing arrangements significantly upgrade the building’s amenity offer. The development delivers modern Category A office space that responds to contemporary occupier expectations, strengthening Wimbledon’s commercial offer in a competitive market.

Neighbouring Amenity and Urban Constraints: Given the site’s position between residential blocks on Hartfield Road and Graham Road, careful consideration was given to daylight, sunlight, privacy and outlook. A BRE-compliant Daylight and Sunlight Assessment confirms that 97% of assessed neighbouring windows meet Vertical Sky Component guidance, with 100% compliance for Annual Probable Sunlight Hours. The stepped rear massing, absence of new flank windows and landscaped terrace design ensure no unacceptable overlooking, enclosure or noise impacts arise. The Council’s pre-application advice confirmed that the proposal would have an acceptable impact on neighbouring amenity.

Sustainability, Energy and Whole Life Carbon: Sustainability underpins the scheme’s design philosophy. The proposals prioritise deep retrofit and reuse of the existing structure, significantly reducing embodied carbon when compared to wholesale redevelopment. Energy efficiency measures include air source heat pumps, mechanical ventilation with heat recovery and roof-mounted photovoltaic panels. The development achieves a 17% carbon reduction beyond Part L 2022 requirements, taking account of retrofit constraints. A Whole Life Carbon Assessment confirms embodied carbon of 312 kgCO₂e/m² to practical completion, approximately half of the GLA’s aspirational benchmark, and the scheme is designed to achieve BREEAM ‘Excellent’.

Urban Greening, Biodiversity and Drainage: The existing building has no on-site greenery. The proposals introduce an extensive green roof and landscaped terrace planters to achieve an Urban Greening Factor of 0.3, delivering measurable environmental enhancement within a fully built-out site. Although exempt from statutory 10% Biodiversity Net Gain due to the de minimis threshold, the scheme provides meaningful biodiversity improvements. Sustainable drainage measures are incorporated through the green roof and planting strategy, reducing surface water runoff in Flood Zone 1 conditions.

Transport and Sustainable Travel: In accordance with London Plan and Local Plan policy for highly accessible town centre locations, the development is car-free. The scheme significantly enhances active travel infrastructure, increasing cycle parking provision from 12 spaces to 60 secure spaces within the basement, alongside new end-of-trip facilities. This exceeds London Plan minimum standards and supports modal shift towards sustainable transport. A Transport Assessment, Travel Plan and Delivery and Servicing Plan confirm that the development will not give rise to severe transport impacts.

A Sustainable Commercial Retrofit for Wimbledon

The Hartfield Road project demonstrates how sensitive vertical extension and comprehensive refurbishment can unlock additional commercial capacity within an established town centre while significantly enhancing design quality, sustainability performance and urban greening. Through a collaborative design and planning process, Maddox Planning secured a policy-compliant scheme that delivers:

• 1,164sqm uplift in Category A commercial floorspace (total 4,088sqm)

• Significant improvement to architectural quality and townscape presence

• High-performance retrofit achieving substantial embodied and operational carbon reductions

• Enhanced biodiversity and sustainable drainage

• A step-change in active travel provision

• Meaningful contribution to Wimbledon Town Centre’s economic vitality

  
  

The scheme represents a benchmark retrofit-led commercial intensification project within outer London, aligning economic growth with environmental responsibility and high-quality urban design.

The scheme represents a benchmark retrofit-led commercial intensification