Chelsfield, Kent
Two-storey rear extension in Chelsfield
Thinking about a two-storey rear extension in Chelsfield? A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Chelsfield and its postcode districts BR5 and BR6 are part of our Kent coverage. In Kent we check the neighbours' rear windows first, because the upper floor is where most two-storey schemes win or lose planning.
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 two-storey rear extension cost in Chelsfield?
A two-storey rear extension in Chelsfield is priced at £2,020–£3,020 per square metre including VAT as a guide, before kitchen fit-out and fees. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £60,500–£90,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £97,000–£145,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a two-storey rear extension in Chelsfield?
Whether your two-storey rear extension in Chelsfield needs a planning application depends on its size, your house and any local restrictions.
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
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 Chelsfield like to extend?
Chelsfield has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.
How a two-storey rear extension in Chelsfield 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Two-storey rear extensions near Chelsfield
Neighbouring places we cover include Orpington (1.7 miles) and Swanley (3.3 miles).
- Two-storey rear extension in Orpington
- Two-storey rear extension in Swanley
- Two-storey rear extension in Bickley
- Two-storey rear extension in Chislehurst
- Two-storey rear extension in Sidcup
Other work in Chelsfield:
FAQ
Two-storey rear extension questions in Chelsfield
What postcode areas do you cover around Chelsfield?
Including BR5 and BR6, and the surrounding Kent area.
How long does a rear extension take to build in Chelsfield?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
What is the 45-degree rule?
Many councils check that a two-storey extension does not cross a 45-degree line drawn from the nearest habitable window of the neighbouring house. We test it at the first drawing.
Can you match the brick or stone on my Chelsfield house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
Do you handle building control in Chelsfield?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
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.