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Greater London

Rear extensions in Welling

We design and build rear extensions for homes in Welling, Greater London, from single-storey kitchen-diners across the back of the house to two-storey extensions that add a bedroom above.

Welling is in Greater London, with postcode districts including DA6, DA15 and DA16. The nearest places we also cover are Abbey Wood (1.7 miles) and Plumstead (1.8 miles).

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Tell us about the house and we'll call to arrange a free, no-obligation visit.

Rear extensions we build in Welling

Also available across Greater London:

Rear extension prices in Welling

London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.

ExampleGuide inc VAT
Single-storey, 3 m × 4 m (12 m²)£29,500–£48,500
Single-storey, 4 m × 6 m (24 m²)£59,500–£96,500
Two-storey, 3 m × 5 m footprint (30 m²)£70,000–£105,500
Side return, about 14 m²£42,000–£69,000
Wraparound, about 25 m²£71,500–£117,000

What are homes in Welling like to extend?

Much of Welling is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.

Planning rules for Welling

English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.

England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.

Planning and Building Regulations are separate in England: even a permitted development extension is inspected for foundations, drainage, structure, insulation, fire safety and ventilation, through the council or a registered building control approver, ending with a completion certificate.

Nearby towns

FAQ

Questions people ask

How much is a rear extension in Welling?

A 3 m × 4 m single-storey rear extension is about £29,500–£48,500 including VAT at our London guide rates; the written price follows a survey.

Do I need planning permission in Welling?

Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.

Is the site visit in Welling free?

Yes, with no obligation.

Do I need a party wall agreement?

In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

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