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Cockfosters, Greater London

Bungalow rear extension in Cockfosters

Bungalow rear extension in Cockfosters: single-storey rear extensions that keep everything on one level. We measure the house, show you what the rules allow, price it in writing and build it.

We cover Cockfosters (EN4, N14 and N20) as part of our Greater London work. For bungalows in Greater London, a rear extension is the usual way to add space without adding stairs.

Book a free site visit

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

How much does a bungalow rear extension cost in Cockfosters?

In Cockfosters, our guide for a bungalow rear extension is £2,400–£3,900 per square metre including VAT for a standard specification. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.

Bungalow rear extension prices in Cockfosters
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£29,000–£47,000
4 m wide × 6 m deep (24 m²)£57,500–£93,500

Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.

Do you need planning permission for a bungalow rear extension in Cockfosters?

Whether your bungalow rear extension in Cockfosters needs a planning application depends on its size, your house and any local restrictions.

In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is 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.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.

What are homes in Cockfosters like to extend?

Much of Cockfosters 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.

How a bungalow rear extension in Cockfosters comes together

  1. Survey visit

    We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.

  2. Drawings and budget

    Floor plans and elevations for the options, each with a guide price.

  3. Paperwork handled

    Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.

  4. Written price, then build

    Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.

Bungalow rear extensions near Cockfosters

We also build rear extensions for bungalows in nearby East Barnet (0.6 miles) and New Barnet (1.2 miles).

Other work in Cockfosters:

All rear extensions in Cockfosters

FAQ

Bungalow rear extension questions in Cockfosters

How much does a bungalow rear extension cost in Cockfosters?

As a guide, £2,400–£3,900 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £29,000–£47,000 at that rate. Your written price follows the survey.

Do you handle building control in Cockfosters?

Yes. We apply to the council or a registered building control approver and hand over the completion certificate.

Can a bungalow extension be fully accessible?

Yes: level thresholds, wider doors and a wet room are straightforward to design in.

Will I need a structural engineer?

Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.

Is the site visit in Cockfosters free?

Yes. We visit, measure up and talk through the options with no cost and no obligation.

Can I get a price without a visit?

Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.

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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