Coulsdon, Greater London
Glazed rear extension in Coulsdon
Full-height glass, slim frames and big rooflights for the most open rear room. We design, get the approvals for and build glazed and glass-box rear extensions in Coulsdon and the surrounding area, with one contract from the first survey to building control sign-off.
Coulsdon and its postcode districts CR5, CR8 and SM6 are part of our Greater London coverage. Glass-led rear extensions in Coulsdon 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 Coulsdon?
A glazed rear extension in Coulsdon 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 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a glazed rear extension in Coulsdon?
The planning route for a glazed rear extension in Coulsdon is set by England's householder rules and your council.
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.
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. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Coulsdon like to extend?
Much of Coulsdon 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 glazed rear extension in Coulsdon 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.
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.
Glazed rear extensions near Coulsdon
From Coulsdon, the nearest places we also cover are Purley (1.7 miles) and Kenley (1.8 miles).
- Glazed rear extension in Purley
- Glazed rear extension in Kenley
- Glazed rear extension in Banstead
- Glazed rear extension in Sanderstead
- Glazed rear extension in Belmont
Other work in Coulsdon:
FAQ
Glazed rear extension questions in Coulsdon
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.
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 there a limit on how much glass I can have?
In England the simple rule is 25% of the floor area plus openings removed; more is allowed with a calculation showing the house still meets Part L.
Can you match the brick or stone on my Coulsdon house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
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.
Is the site visit in Coulsdon free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.