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Improving at NW11 7TL

What you could build at NW11 7TL: the planning rules at this address, what neighbours have built and how big, planning decisions nearby, rough costs and the value an extension adds, and how to get started. In Temple Fortune, Barnet.

100extensions seen within 600 m in the last 10 years

13loft conversions within 600 m in the last 10 years

76%of 165 householder applications nearby approved (since 2023)

88.4extensions per 1,000 homes in the neighbourhood (10 years)

● work seen on energy certificates · ● application approved · ● refused · ● pending or other · ● this postcode

The rules at this address

Mostly flats at this postcode. Flats have no permitted development rights, so almost any extension or loft conversion needs planning permission, and the freeholder's consent under the lease.
In the Hampstead Garden Suburb conservation area: permitted development is narrower (for example no side extensions or roof cladding), and demolition and works to trees need consent.
Article 4 direction (Article 4 Small Houses in Multiple Occupation (HMO) Area 1; Article 4 for Hampstead Garden Suburb CA Area 1): some rights normally allowed have been removed here. Check what it covers with the council before relying on permitted development.
Listed buildings need listed building consent for most changes, inside and out: check the National Heritage List.
To be certain work is permitted development, apply for a lawful development certificate (about £129 for householders in England). Building regulations apply either way.

What neighbours have built

Home	Work	Seen	Space added	Floor area	Rooms	Distance
11a, Temple Fortune Lane	Extension	2026	+56 m²	111 m² → 167 m²	4 → 6	311 m
49, St Georges Road	Extension	2026	+34 m²	157 m² → 191 m²	8 → 6	339 m
45, St Georges Road	Extension	2026	+70 m²	119 m² → 189 m²	6 → 8	339 m
1, Highcroft Gardens	Extension	2026	+58 m²	141 m² → 199 m²	6 → 8	384 m
26, Oakfields Road	Extension	2026	+169 m²	281 m² → 450 m²	–	413 m
50, Leeside Crescent	Extension	2026	+49 m²	132 m² → 181 m²	–	424 m

Planning applications nearby

Address	Work	Outcome	Decided	Drawings and agent
50, Brookside Road, Nw11 9ne	Rear extension	Under consideration	–	26/3653/PNH
109, Wentworth Road, Nw11 0rh	Rear extension	Under consideration	–	26/3573/HSE
29, Temple Fortune Hill, Nw11 7xl	Other householder work	Under consideration	–	26/3525/HSE
12, Park Way, Nw11 0ex	Rear extension	Under consideration	–	26/3541/PNH
14, Cranbourne Gardens, Nw11 0hp	Rear extension	Under consideration	–	26/3475/PNH
22, Highcroft Gardens, Nw11 0lx	Rear extension	Under consideration	–

How often householder applications are approved

Work	Temple Fortune	Barnet	London	Typical decision time
All householder applications	84% (198)	76% (5649)	80%	8 weeks
Loft or dormer	88% (58)	81% (1882)	81%	8 weeks
Rear extension	58% (40)	66% (1643)	79%	8 weeks
Two-storey extension	79% (14)	74% (662)	72%	8 weeks
Other householder work	92% (12)	65% (389)	70%	8 weeks
Side return or wrap-around	88% (8)	85% (148)	88%	8 weeks
Windows, doors or cladding	95% (43)	95% (317)	90%	8 weeks
Outbuilding or garden room	–	81% (108)	79%	8 weeks
Side extension	–	94% (120)	86%	8 weeks
Garage conversion or garage

Cost and the value it adds

Across England and Wales, homes extended by a typical 30 m² and then resold rose about 11.1% more than similar homes nearby over the same years (124,884 resales). How extensions pay off by size, type and region.

Single-storey rear or side extension: about £2,000–£3,000 per m² (London £2,500–£4,000), plus fees and VAT
Loft conversion: about £45,000–£75,000 for a dormer; more for a mansard or hip-to-gable
Two-storey extension: about £1,800–£2,800 per m² of new floor
Garage conversion: about £15,000–£30,000
Basement: about £3,500–£5,000 per m², London mostly

Build costs are rough 2026 ranges from industry guides, not quotes. Get three quotes for your plans.

Move or improve?

The money you don't get back either way, for the same extra space in Temple Fortune.

Your home is worthExtra space you need (m²)Homes here sell for, per m²Building cost per m²Share of that an extension adds (%)

Move to a home 20 m² bigger (about £1,213,000)

Stamp duty on the new home	£65,050
Estate agent on yours 1.2% + VAT	£14,760
Solicitors, buying and selling	£3,000
Survey	£600
Removals	£1,500
Money gone	£84,910

Extend by 20 m²

Building, plus 15% for design, planning and contingency	£57,500
Less what it adds to your home's value 60% of the local price	−£112,800
Money gone	−£55,300

On these figures, extending loses about £140,210 less. Moving also changes the area, the schools and the commute; extending means months of building work and depends on planning.

Building costs vary a lot (a single-storey rear extension is often £2,000–£3,000 per m², more in London). How much space adds depends on the home and street: what extensions added to resale prices. A guide, not advice; nothing you type leaves this page.

Getting started

Look at what neighbours did. Open applications above to see drawings that were approved on similar houses, and who designed them.
Check the route: permitted development (with a lawful development certificate), prior approval for larger rear extensions, or full householder planning permission.
Get a measured survey and a designer: an architect, an architectural technologist or a designer who handles planning drawings.
Apply (householder permission is about £258 in England; councils aim to decide within 8 weeks).
Building regulations through the council's building control or an approved inspector, and party wall notices to neighbours if you build on or near the boundary.
Choose a builder: written quotes, a contract, staged payments, and check their insurance and references.

Find help: RIBA Find an Architect ↗ · CIAT architectural technologists ↗ · TrustMark tradespeople ↗ · Federation of Master Builders ↗ · Planning Portal guides ↗

General guidance, not planning or legal advice. Fees and rules as checked in October 2026; confirm with the council.

Energy certificates: MHCLG (OGL). Planning applications: GLA Planning London Datahub. Conservation areas and Article 4: planning.data.gov.uk (OGL).

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Improving at NW11 7TL

The rules at this address

What neighbours have built

Planning applications nearby

How often householder applications are approved

Cost and the value it adds

Move or improve?

Getting started

Go deeper

Improving at NW11 7TL

NW11 7TL is on Finchley Road

The rules at this address

What neighbours have built

Planning applications nearby

How often householder applications are approved

Cost and the value it adds

Move or improve?

Getting started

Go deeper

NW11 7TL is on Finchley Road