Conservatory replacement extensions across Northolt
A conservatory replacement in Northolt starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in NortholtFrom £26,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–14 weeks on site
- Postcode districtsHA2, UB5, UB6

Will the council need to approve it?
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Conservatory replacement prices in Northolt
Prices below are for Northolt, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Northolt: £2,400 to £4,550 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 3.3 m 10 m² | £26,000 – £31,000 | £27,500 – £36,000 | £35,500 – £45,500 |
| 3.5 m × 4 m 14 m² | £33,500 – £40,500 | £39,000 – £50,500 | £50,000 – £64,000 |
| 4 m × 5 m 20 m² | £48,000 – £57,500 | £55,500 – £71,500 | £71,500 – £91,000 |
Includes removal of the old conservatory. Reusing existing foundations is only possible after investigation.
For a figure based on your own dimensions, use our guide-price tool.
What is included
- Trial holes to check the existing foundations
- Glazing and doors to suit the new room
- Insulated walls and roof to current regulations
- Removal and disposal of the old conservatory
- New or upgraded foundations
Covering Northolt
We cover Northolt and the postcode districts HA2, UB5, UB6. Nearby, we also take on projects in Greenford (1 mile), South Ruislip (2 miles), Harrow (3 miles), Southall (3 miles).
Bushey, in Hertfordshire, is roughly 7 miles from Northolt and also on our list. London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
From first visit to completion
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
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.
Questions people ask about conservatory replacements
How long does a conservatory replacement take to build in Northolt?
On site, typically 8 to 14 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Who do I contract with for a conservatory replacement in Northolt?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Northolt, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
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.
Does replacing a conservatory need planning permission?
A solid replacement is treated as a new extension, so it must meet the permitted development limits or get planning permission, and it always needs building regulations approval.
Book a free site visit in Northolt
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.