Mansfield Street, W1G

Property Summary

Occupying one of Marylebone’s most distinguished streets, this seven-bedroom freehold townhouse extends to approximately 13,495 sq ft across five principal floors. Completed in 1773 by Robert Adam, the house preserves its Georgian architectural character — soaring ceilings, marble fireplaces and intricate plasterwork — while incorporating considered contemporary interventions throughout. The ground floor centres on a kitchen and reception arrangement connected by wedding doors, opening rearward to a private terrace and discreet garage. The first floor is given over to formal entertaining, with twin reception rooms, a study and a library. The principal suite on the second floor includes a marble bathroom, dressing room and guest suite, while the third floor accommodates five further bedrooms, sitting and TV rooms, and a mezzanine library at the crown of the house. The lower ground level provides additional flexibility with two self-contained studios, a gym and four vaults.

Key Features

• Grade II listed Georgian townhouse completed in 1773 by Robert Adam
• Approximately 13,495 sq ft across five principal floors
• Seven bedrooms and seven bathrooms
• Formal first-floor entertaining suite with twin reception rooms, study and library
• Principal suite with marble bathroom, freestanding bath and bespoke dressing room
• Ground-floor kitchen with reception rooms linked by wedding doors
• Private rear terrace with discreet garage
• Two self-contained lower ground floor studios, one with kitchenette
• Dedicated gym and plant room at lower ground level
• Four basement vaults
• Mezzanine library crowning the top of the house
• Original marble fireplaces, intricate plasterwork and soaring ceilings throughout
• Freehold tenure
• EPC Rating C
• Marylebone High Street, Regent’s Park and major transport links within close reach

Design Comment

Mansfield Street represents one of the more compelling propositions in central London for a buyer intent on creating a truly singular family residence. The Robert Adam provenance and surviving 18th-century detailing — the plasterwork, the marble chimney pieces, the generous ceiling heights — provide a foundation of architectural integrity that is increasingly rare at this scale. At approximately 13,495 sq ft across five floors, the house offers the volume and vertical separation necessary for a comprehensive interior design scheme that distinguishes formal entertaining spaces from private family quarters without compromise.

The existing layout demonstrates intelligent spatial planning, particularly the wedding-door arrangement linking reception rooms on both the ground and first floors, which allows for fluidity between intimate and large-scale gatherings. The kitchen, with its bold lime green island, signals that the house has already undergone a degree of contemporary reinterpretation. A new owner would have the opportunity to refine and elevate these interventions, potentially reworking material palettes, joinery and lighting to establish a more cohesive dialogue between the Georgian shell and a sophisticated modern interior. The principal suite, with its marble bathroom and bespoke dressing room, is well proportioned but could benefit from a holistic design review to introduce the level of finish — heated stone floors, integrated lighting, bespoke sanitaryware — that a residence of this calibre warrants.

The lower ground floor, with its self-contained studios, gym and four vaults, presents significant scope for creative programming. The vaults in particular could be reimagined as a home cinema, wine cellar, home spa or secure storage, depending on the buyer’s priorities. Throughout the house, a carefully considered lighting strategy, sympathetic restoration of original features and the introduction of high-specification environmental systems would allow this Adam townhouse to perform as a contemporary family home of the highest order.

Development Consultations

To assist potential buyers of this property to understand their full design and development options, Janine Stone & Co. is able to provide complimentary design concept and development consultations. It can be arranged for these consultations to take place at the property or in our London studio. Janine Stone & Co. will provide guidance on architecture, refurbishment and planning considerations, in addition to helping interested parties to develop their early design ideas into floor plans with estimated project costs and timelines for realisation.

Should a successful acquisition take place, we would be happy to take these initial concepts through to a full concept and subsequent planning, design and build phases.