Conservatory replacement extensions across St Albans
Our design and build teams take on conservatory replacements in St Albans, from the first measured survey through planning and building control to the finished room.
- Guide price in St AlbansFrom £21,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–14 weeks on site
- Postcode districtsAL1, AL2, AL3, AL4

How much does a conservatory replacement cost in St Albans?
For St Albans we adjust our national guide rates by ×1.06, the factor we use for East of England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in St Albans: £1,960 to £3,710 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 3.3 m 10 m² | £21,000 – £25,500 | £22,500 – £29,500 | £29,000 – £37,500 |
| 3.5 m × 4 m 14 m² | £27,000 – £33,000 | £31,500 – £41,000 | £40,500 – £52,000 |
| 4 m × 5 m 20 m² | £39,000 – £47,000 | £45,500 – £58,500 | £58,000 – £74,500 |
Includes removal of the old conservatory. Reusing existing foundations is only possible after investigation.
Want a range for your exact size? The guide-price tool takes about a minute.
Do I need planning permission in St Albans?
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).
Is a conservatory replacement right for your house?
- Conservatories that are too hot or too cold
- Homes where the conservatory sits unused
- Older uPVC conservatories near the end of their life
Extensions in and around St Albans
Postcode districts we cover around St Albans include AL1, AL2, AL3, AL4. Nearby, we also take on projects in Harpenden (5 miles), Hatfield (5 miles), Hemel Hempstead (5 miles), Welwyn Garden City (6 miles).
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
What happens next
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Your questions about a conservatory replacement in St Albans
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for St Albans, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in St Albans 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 St Albans?
Yes. We cover St Albans and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
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 St Albans
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.