A house extension can transform your home, adding valuable living space. Costs cover foundations, structural work, roofing, glazing, internal fit-out, and connection to existing services. In Marylebone (W1, NW1), costs reflect the area's Inner London market position, with a 5% premium over London averages.
Marylebone is a refined central London village with elegant Georgian terraces, the famous High Street, and a vibrant food scene. It combines metropolitan convenience with residential tranquillity.
| Specification | Price per sqm | Typical 25sqm Project | Includes |
|---|---|---|---|
|
Standard
Quality materials, clean design
|
£2,625 – £3,360 | £65,625 – £84,000 | All structural work, standard fixtures, full fit-out and decoration |
|
Premium
Designer brands, bespoke elements
|
£3,360 – £4,200 | £84,000 – £105,000 | Premium materials, designer fixtures, underfloor heating, smart controls |
|
Luxury
Finest materials, fully bespoke
|
£4,200 – £5,775 | £105,000 – £144,375 | Bespoke joinery, natural stone, top-tier appliances, architectural detailing |
Prices include VAT and are based on Marylebone (W1, NW1) market rates. Prices reflect Inner London market conditions and local construction costs. Actual costs depend on site-specific factors. All prices are guide estimates for 2025.
Here's what a typical 25sqm house extension project would cost in Marylebone at each specification level.
Marylebone falls largely within the Portman Estate and Howard de Walden Estate conservation areas. Georgian facades and street patterns are rigorously protected.
Key streets and roads in Marylebone include Marylebone High Street, Wimpole Street, Devonshire Place, Manchester Square, Montagu Square. Properties in these locations often have specific architectural characteristics that influence renovation costs, including estate leasehold requirements and approvals, Georgian terraced property expertise needed, central London construction logistics, Westminster planning policies.
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