Conservatory replacement extensions across Farnworth
Our design and build teams take on conservatory replacements in Farnworth, from the first measured survey through planning and building control to the finished room.
- Guide price in FarnworthFrom £19,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–14 weeks on site
- Postcode districtsBL3, BL4, M38

Planning and approvals in Farnworth
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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).
What should I budget for a conservatory replacement in Farnworth?
Labour and material costs vary across the UK, so for Farnworth we use our North West England factor (×0.95). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Farnworth: £1,760 to £3,320 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 3.3 m 10 m² | £19,000 – £23,000 | £20,000 – £26,500 | £26,000 – £33,500 |
| 3.5 m × 4 m 14 m² | £24,500 – £29,500 | £28,500 – £37,000 | £36,500 – £47,000 |
| 4 m × 5 m 20 m² | £35,000 – £42,000 | £40,500 – £52,500 | £52,000 – £66,500 |
Includes removal of the old conservatory. Reusing existing foundations is only possible after investigation.
Try the guide-price tool to see a range for your own size and finish.
Covering Farnworth
We cover Farnworth and the postcode districts BL3, BL4, M38. We also work in nearby Walkden (2 miles), Bolton (3 miles), Radcliffe (3 miles), Tyldesley (4 miles).
Golborne, in Merseyside, is roughly 10 miles from Farnworth and also on our list. Across the North West, terraced houses with small rear yards suit compact rear and side return extensions, while suburban semis have room for more.
Who a conservatory replacement suits
- Older uPVC conservatories near the end of their life
- Conservatories that are too hot or too cold
- Homes where the conservatory sits unused
A replacement is a chance to rethink the shape. Many conservatories are oddly proportioned; for a similar cost the new room can often be squarer, wider or better connected to the kitchen.
How the project works
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
We visit your Farnworth home, measure up, talk through what you want and check the planning position.
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in Farnworth
Will my neighbours in Farnworth 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.
Do you cover all of Farnworth?
Yes. We cover Farnworth and the surrounding parts of Greater Manchester. Site visits are free and there is no obligation.
Do I need building regulations approval in Farnworth?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Is it worth replacing a conservatory with an extension?
If the conservatory is unusable for much of the year, usually yes. A solid extension gives a heated room that counts as proper living space. Our guide range is about £1,760 to £3,320 per m² including VAT, including removal.
Can I keep the existing base?
Sometimes, but conservatory bases are often too shallow for solid walls. Trial holes tell us before we confirm the price.
Book a free site visit in Farnworth
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.