Nailsea, Somerset
Two-storey rear extension in Nailsea
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. If you live in Nailsea and want to know what a two-storey rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Nailsea is covered from our Somerset round, including BS48. In Nailsea, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted.
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 Nailsea?
Guide prices for a two-storey rear extension in Nailsea start from our South West England rate of £1,870–£2,810 per square metre, including VAT. South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £56,000–£84,000 |
| 4 m × 6 m footprint, two floors (48 m²) | £90,000–£135,000 |
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 two-storey rear extension in Nailsea?
Here is how the rules in England apply to a two-storey rear extension in Nailsea.
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 Nailsea like to extend?
Nailsea has Victorian terraces nearer the centre and post-war semis on the edges. Sloping gardens are frequent, which affects floor levels and steps down to the patio.
How a two-storey rear extension in Nailsea 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.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
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.
Two-storey rear extensions near Nailsea
Neighbouring places we cover include Portishead (3.5 miles) and Yatton (4.1 miles).
- Two-storey rear extension in Portishead
- Two-storey rear extension in Yatton
- Two-storey rear extension in Clevedon
- Two-storey rear extension in Bishopsworth
- Two-storey rear extension in Bristol
Other work in Nailsea:
FAQ
Two-storey rear extension questions in Nailsea
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 the site visit in Nailsea free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Is two-storey cheaper per square metre than single-storey?
Usually yes, because the foundations and roof are shared across twice the floor area. The total cost is higher.
Do you handle building control in Nailsea?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How long does a rear extension take to build in Nailsea?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do I need planning permission for a rear extension in Nailsea?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.