Chalfont St Peter, Buckinghamshire
Glazed rear extension in Chalfont St Peter
Glazed rear extension in Chalfont St Peter: full-height glass, slim frames and big rooflights for the most open rear room. We measure the house, show you what the rules allow, price it in writing and build it.
Chalfont St Peter sits in Buckinghamshire, with postcode districts including SL9. If your garden in Chalfont St Peter faces south, expect us to talk about overhangs and solar-control glass before frame colours.
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 Chalfont St Peter?
For Chalfont St Peter we work from the South East England rate: £3,140–£5,380 per square metre of new floor, including VAT, standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £37,500–£64,500 |
| 4 m wide × 6 m deep (24 m²) | £75,500–£129,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a glazed rear extension in Chalfont St Peter?
The planning route for a glazed rear extension in Chalfont St Peter is set by England's householder rules and your council.
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. 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 Chalfont St Peter like to extend?
Commuter semis and detached houses make up much of Chalfont St Peter, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a glazed rear extension in Chalfont St Peter comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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 Chalfont St Peter
We also build glazed and glass-box rear extensions in nearby Gerrards Cross (1.6 miles) and Chorleywood (3.6 miles).
- Glazed rear extension in Gerrards Cross
- Glazed rear extension in Chorleywood
- Glazed rear extension in Beaconsfield
- Glazed rear extension in Rickmansworth
- Glazed rear extension in Batchworth
Other work in Chalfont St Peter:
FAQ
Glazed rear extension questions in Chalfont St Peter
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.
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 a glass box a conservatory?
No. It is built to Building Regulations as part of the house, with insulated floor and roof, so it is usable all year.
What postcode areas do you cover around Chalfont St Peter?
Including SL9, and the surrounding Buckinghamshire area.
Can you match the brick or stone on my Chalfont St Peter house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
How long does a rear extension take to build in Chalfont St Peter?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.