Annexe extensions in Atherton
Planning an annexe extension in Atherton? We survey the house, work out the planning route, draw the design and build it, so you deal with one team from the first visit to the completion certificate.
- Guide price in AthertonFrom £52,000 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsBL5, M29, M46, WN7
Included in a typical project
- Separate or shared heating and hot water
- Design for accessibility: level thresholds, wider doors, walk-in shower
- Fire separation and alarms to building regulations
- Kitchenette, shower room and bedroom finish
Covering Atherton
Postcode districts we cover around Atherton include BL5, M29, M46, WN7. We also work in nearby Tyldesley (1 mile), Westhoughton (2 miles), Leigh (2 miles), Hindley (4 miles).
Across the North West, terraced houses with small rear yards suit compact rear and side return extensions, while suburban semis have room for more.
How much does an annexe extension cost in Atherton?
These guide figures apply our North West England adjustment (×0.95) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Atherton: £1,900 to £3,610 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £52,000 – £65,500 | £57,000 – £71,500 | £71,000 – £90,500 |
| One-bedroom annexe 35 m² | £66,500 – £83,500 | £79,500 – £100,000 | £99,500 – £126,500 |
| Larger annexe 45 m² | £85,500 – £107,000 | £102,500 – £128,500 | £128,000 – £162,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Will the council need to approve it?
In England an annexe that stays part of the household and connects to the house is assessed as an extension, but its size usually takes it beyond permitted development, so a householder application describing the ancillary use is the normal route.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Annexe extension questions answered
Do you cover all of Atherton?
Yes. We cover Atherton and the surrounding parts of Greater Manchester. Site visits are free and there is no obligation.
Do I need building regulations approval in Atherton?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Will my neighbours in Atherton be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Does an annexe extension need planning permission?
Usually yes, because of its size and the way it will be used. Councils check that it stays ancillary to the main house, so the application must describe the use clearly.
Can the annexe have its own front door?
Yes, many do, but it should still connect to the main house to stay clearly part of it.
Book a free site visit in Atherton
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.