Project showcase · Hampstead NW6
Hampstead NW6 — Penthouse Duplex Loft Conversion with Roof Terrace
Roof demolition and rebuild · Duplex penthouse creation · Panoramic London views · Completed 2025
Introduction
Creating a luxury penthouse duplex on the 5th floor in Hampstead
Hampstead is one of London's most desirable addresses — known for its elevated position, village character and some of the capital's finest residential properties. This project, completed in 2025, took a top-floor flat on the fifth floor of a residential block and transformed it into something far more rare and valuable: a luxury duplex penthouse with private roof terrace and panoramic views across London.
This was not a conventional loft conversion. There was no existing loft space to convert. LCCL Construction's team had to completely demolish the existing roof structure, engineer and build an entirely new roof at a higher level incorporating a full habitable loft floor, and then structurally connect the new upper level to the existing fifth-floor flat below — creating a two-storey duplex penthouse with internal staircase from scratch.
The result is a property that is genuinely exceptional — a penthouse duplex in Hampstead NW6, high above the city, with Lusso Stone bathrooms, engineered wood floors, oak stairs, sliding thin-profile doors, picture windows and a private roof terrace from which the London skyline stretches in every direction.
Before and After
Before
During
Completed
The challenge
Demolishing a roof on a live residential block
Demolishing a roof on a live residential block is one of the most technically and logistically demanding operations in residential construction. Every flat below remains occupied. The building must be protected from weather at all times. The structural integrity of the block must be maintained throughout. And the works must be sequenced and managed to minimise disruption to residents in a way that a standard site simply does not require.
LCCL Construction installed temporary weatherproofing immediately following demolition of the existing roof — a critical step that required precise planning and a rapid mobilisation of the weatherproofing team to ensure the building was never left exposed. The structural engineering solution for the new roof had to work entirely within the load-bearing capacity of the existing block, requiring bespoke steel connections and careful coordination with the building's structural engineer and freeholder.
The roof terrace required a fully specified waterproof deck system with integrated drainage — designed to guarantee that no water could penetrate to the apartment below. At five floors above ground level, the terrace also required carefully engineered balustrade and wind screening solutions to meet building regulations and planning requirements while preserving the open, panoramic quality of the space.
Planning and freeholder consents, party wall considerations for a block of flats, structural calculations for the new roof, building control sign-off across all phases — LCCL Construction managed every approval and every trade under a single design and build contract.
Scope of works
- Full architectural design, planning application and freeholder consent management
- Structural engineering — new roof structure, load transfer calculations, bespoke steel connections
- Building control throughout all phases — completion certificate issued
- Project management — single point of contact, resident liaison throughout
- Complete demolition of existing roof structure
- Temporary weatherproofing installed immediately post-demolition
- New roof structure engineered and built to new specification
- New loft habitable floor created within new roof volume
- Structural connection between new loft level and existing 5th floor flat
- New internal staircase — oak treads — creating duplex access
- Roof terrace — waterproof deck system, drainage, glazed balustrade and wind screening
- Picture windows installed to maximise London views
- Sliding thin-profile internal doors throughout
- 2 new bedrooms at loft level
- 2 new Lusso Stone bathrooms — fully tiled floor to ceiling
- Open plan living and reception space
- Full rewiring and new electrical installation to loft level
- Plumbing and heating extended to loft level
- Engineered wood floors throughout loft level
- Complete interior fit-out and high-end decoration throughout
Design & specification
Contemporary specification with panoramic London views
The interior specification was chosen to reflect the exceptional position and calibre of the property. Engineered wood floors run throughout the loft level — warm, durable and architecturally consistent with the contemporary finish. Oak stairs connect the two levels, their natural grain and clean profile a deliberate counterpoint to the crisp white walls and slim-profile internal doors.
Lusso Stone bathrooms — fully tiled floor to ceiling — deliver a spa-quality finish in every wet room. Lusso Stone is a premium British brand known for its stone resin baths, basins and shower trays, and its specification signals a commitment to quality that discerning buyers and tenants recognise immediately.
Sliding thin-profile doors were specified throughout to maximise floor area in what is, by definition, a carefully optimised space. Their slim frames and large glass panels allow light to move freely between rooms while maintaining the sense of defined, purposeful spaces. Picture windows at the loft level were positioned to frame the London skyline — not as an afterthought, but as a central element of the architectural brief.
The roof terrace completes the picture. Accessible from the loft level, it is a private outdoor space at elevation — rare in London, exceptional in Hampstead — with views that on a clear day extend across the entire city.
Finished project gallery
Outcome
A luxury duplex penthouse in Hampstead NW6
A single top-floor apartment has been transformed into one of the area's most desirable properties — a luxury duplex penthouse with private roof terrace and unobstructed panoramic views across London. The increase in property value is significant; duplex penthouses with outdoor space command a substantial premium over conventional top-floor flats in NW6.
- Single flat converted to full two-storey duplex penthouse
- Private roof terrace with panoramic London views
- Oak staircase connecting duplex levels
- Engineered wood floors throughout
- Sliding thin-profile doors throughout
- Picture windows framing London skyline
- Significantly increased property value
About LCCL Construction
About LCCL Construction
LCCL Construction is a LABC Award-winning design and build company based in Finchley, London N3, specialising in loft conversions, house extensions, luxury renovations and complex structural projects across London and Hertfordshire. With over 20 years of experience, 200+ verified reviews rated 4.7/5, and optional 10-year LABC warranties, we have the expertise to deliver projects of this complexity to the highest standard.
Call 020 8037 7332 or visit lcclconstruction.co.uk to book your free consultation.
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