Chalk Farm, Greater London
Glazed rear extension in Chalk Farm
Full-height glass, slim frames and big rooflights for the most open rear room. If you live in Chalk Farm and want to know what a glazed rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Chalk Farm sits in Greater London, with postcode districts including NW1, NW3 and NW5. Glass-led rear extensions in Chalk Farm are planned around which way the garden faces, because that decides the glass specification.
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 glazed rear extension cost in Chalk Farm?
A glazed rear extension in Chalk Farm is priced at £3,640–£6,240 per square metre including VAT as a guide, before kitchen fit-out and fees. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £43,500–£75,000 |
| 4 m wide × 6 m deep (24 m²) | £87,500–£150,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a glazed rear extension in Chalk Farm?
Planning for a glazed rear extension in Chalk Farm follows the English householder rules.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
New fabric must meet Approved Document L (2021 edition incorporating 2023 amendments): walls 0.18, roof 0.15 and floor 0.18 W/m²K, windows 1.4 W/m²K or Band B. Under the simple route, new windows, doors and rooflights should not exceed 25% of the extension floor area plus any openings removed; more glass is possible with a whole-house calculation.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Chalk Farm like to extend?
Period terraces in Chalk Farm sit alongside flats, and the difference matters: houses usually keep permitted development rights, while flats and maisonettes need planning permission for any rear extension.
How a glazed rear extension in Chalk Farm comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Glazed rear extensions near Chalk Farm
We also build glazed and glass-box rear extensions in nearby Camden Town (0.3 miles) and Belsize Park (1.0 miles).
- Glazed rear extension in Camden Town
- Glazed rear extension in Belsize Park
- Glazed rear extension in Holloway
- Glazed rear extension in Barnsbury
- Glazed rear extension in Highgate
Other work in Chalk Farm:
FAQ
Glazed rear extension questions in Chalk Farm
How much does a glazed rear extension cost in Chalk Farm?
As a guide, £3,640–£6,240 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £43,500–£75,000 at that rate. Your written price follows the survey.
Is the site visit in Chalk Farm free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Can I have a level threshold?
Yes, with a drainage channel outside the doors and the slab set to the patio level.
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.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
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.