House Extensions Chiswick W4 2026: Complete Guide to Costs, Planning and Types
Chiswick is one of West London's most desirable and architecturally rich residential areas, sitting in the W4 postcode along the River Thames between Hammersmith, Acton, Turnham Green and Kew. The area is characterised by beautiful Victorian and Edwardian terraces, elegant Edwardian villas around Bedford Park and modern riverside apartments — with consistently strong property values driving substantial demand for extensions. Chiswick's excellent District line and Piccadilly line connections, thriving Chiswick High Road and family-friendly schools make house extensions here one of West London's best investments. LCCL Construction delivers house extensions across Chiswick and all of West London as part of our complete design and build service.
Best House Extension Types for Chiswick W4 Properties
Chiswick's Victorian and Edwardian terraces are ideally suited to wraparound extensions combining rear and side return for maximum ground floor space. The larger Edwardian villas around Bedford Park and Grove Park suit double storey extensions that transform three-bedroom family homes into substantially larger properties.
House Extension Costs in Chiswick W4 in 2026
Chiswick pricing runs slightly above outer London due to premium location. Rear extension: £45,000 to £85,000. Side return: £45,000 to £85,000. Wraparound: £70,000 to £145,000. Double storey: £95,000 to £185,000. All include full design and build. See our full home extension cost guide.
Planning Permission for House Extensions in Chiswick
Chiswick has extensive conservation area coverage — Bedford Park was one of the first designated conservation areas in the UK and remains particularly strict, with Grove Park, Chiswick Mall, Old Chiswick and Strand-on-the-Green all requiring careful planning. Article 4 directions further restrict permitted development rights in specific streets. The London Borough of Hounslow is the planning authority. Most house extensions in Chiswick W4 require full planning permission. LCCL Construction handles all planning applications and conservation area consultations.
How Much Value Does an Extension Add in Chiswick?
Chiswick property values are among the highest in West London. A wraparound extension costing £100,000 typically adds £200,000-£350,000+ to the value of a Chiswick Victorian terrace. A double storey extension costing £140,000 typically adds £260,000-£450,000+. Extensions in premium Chiswick streets around Bedford Park and near the river deliver exceptional returns. See our full guide on how much value an extension adds.
Areas Around Chiswick We Cover
LCCL Construction covers Chiswick W4, Bedford Park W4, Grove Park W4, Chiswick Park W4, Turnham Green W4, Gunnersbury W4, Strand-on-the-Green W4, Hammersmith W6, Acton W3, Ealing W5 W13, Brentford TW8, Kew TW9, Barnes SW13, Fulham SW6 and all surrounding West London postcodes.
Frequently Asked Questions About House Extensions in Chiswick
How much does a house extension cost in Chiswick W4?
From £45,000 for a small rear extension to £185,000+ for a large double storey. A typical wraparound costs £70,000 to £145,000.
Do I need planning permission for an extension in Chiswick?
Yes — most extensions in Chiswick W4 require planning permission due to extensive conservation area coverage across Bedford Park, Grove Park and Chiswick Mall.
To book a free consultation for your Chiswick extension call LCCL Construction on 020 8037 7332 or get an instant quote online.
