Loft Conversions & House Extensions Swiss Cottage NW3 & West Hampstead NW6 2026
- LCCL Construction
- 6 hours ago
- 2 min read
Swiss Cottage and West Hampstead are two of North London's most sought-after residential neighbourhoods, sitting adjacent to Hampstead NW3 and Belsize Park in the NW3 and NW6 postcodes. Both areas are characterised by large Victorian and Edwardian terraced and semi-detached houses with high property values, strong buyer demand and excellent transport links into central London. LCCL Construction delivers loft conversions and house extensions across Swiss Cottage, West Hampstead and all surrounding areas as part of our complete design and build service.
Loft Conversions Swiss Cottage NW3: Best Types and Costs
Swiss Cottage has a mix of large Victorian terraced houses and inter-war mansion blocks. The Victorian terraces suit dormer, L-shaped dormer and mansard loft conversions. Given the high property values in NW3, a mansard is often the best investment for properties where maximum space and value uplift is the priority. Costs range from £30,000 for a Velux to £140,000 for a high-specification mansard. See our full loft conversion cost guide for a detailed breakdown.
House Extensions Swiss Cottage NW3: Best Types and Costs
Victorian terraced houses in Swiss Cottage suit rear extensions, side return extensions and wraparound extensions. A wraparound extension creating an open plan ground floor typically costs £70,000 to £115,000. See our full house extension cost guide.
Loft Conversions West Hampstead NW6: Best Types and Costs
West Hampstead NW6 has a high concentration of Victorian terraced houses with back additions making it ideal for L-shaped dormer loft conversions. The NW6 postcode also extends into Maida Vale and Kilburn where large Victorian terraces suit dormer and mansard conversions. Costs in West Hampstead are broadly in line with NW3 given the premium location and high property values.
Planning Permission in Swiss Cottage and West Hampstead
Both Swiss Cottage and West Hampstead fall within the London Borough of Camden which has extensive conservation area coverage. Planning permission is required for many loft conversions and extensions in these areas. LCCL Construction checks all planning requirements as part of the free consultation. See our full guide to loft conversion planning permission in London and our guide to house extension planning permission in London.
Areas Around Swiss Cottage and West Hampstead We Cover
LCCL Construction covers Swiss Cottage NW3, West Hampstead NW6, Hampstead NW3, Belsize Park NW3, Primrose Hill NW1, St John's Wood NW8, Maida Vale NW6, Kilburn NW6, Finchley Road NW3, Golders Green NW11, Cricklewood NW2 and all surrounding postcodes.
Frequently Asked Questions
How much does a loft conversion cost in Swiss Cottage?
Costs range from £30,000 for a Velux to £140,000 for a high specification mansard. A typical dormer with en-suite costs £52,000 to £75,000.
To get a free consultation call LCCL Construction on 020 8037 7332 or get an instant quote online.
