Conservatory replacement extensions across County Londonderry
Thinking about a conservatory replacement for your County Londonderry home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide priceFrom £17,000 inc VAT
- PlanningNI permitted development (rear 3–4 m) or planning
- Towns covered4
- Site visitFree, no obligation

Towns in County Londonderry
What should I budget for a conservatory replacement in County Londonderry?
For County Londonderry we adjust our national guide rates by ×0.86, the factor we use for Northern Ireland. Figures include VAT; your written quote after the survey replaces them.
Typical rates in County Londonderry: £1,590 to £3,010 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 3.3 m 10 m² | £17,000 – £20,500 | £18,000 – £24,000 | £23,500 – £30,500 |
| 3.5 m × 4 m 14 m² | £22,000 – £26,500 | £25,500 – £33,500 | £33,000 – £42,500 |
| 4 m × 5 m 20 m² | £31,500 – £38,000 | £36,500 – £47,500 | £47,000 – £60,500 |
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.
Working in County Londonderry
Towns we cover in County Londonderry include Derry/Londonderry, Coleraine, Limavady, Magherafelt. In Northern Ireland, extension projects follow the NI planning rules and council building control, which we account for from the first survey.
Planning and approvals in County Londonderry
In Northern Ireland the Planning (General Permitted Development) Order 2015 lets some single-storey rear extensions go ahead without planning permission, up to 3 m on a semi-detached or terraced house and 4 m on a detached house, within height and boundary limits. Larger, side and two-storey extensions normally need planning permission from the council, and building control approval is separate.
Homes in conservation areas, areas of townscape character and listed buildings have tighter rules, so we always check the property's status and planning history before design starts.
Northern Ireland has no Party Wall Act. Where work is on or close to a shared boundary, we agree access and protection with your neighbour in writing before work starts.
In Northern Ireland building control is run by the councils under the Building Regulations (Northern Ireland). We submit full plans or a building notice and book the inspections through to completion.
Applications are decided by your council, which handles local planning in Northern Ireland.
Included in a typical project
- Insulated walls and roof to current regulations
- Removal and disposal of the old conservatory
- Opening widened into the house if wanted
- New or upgraded foundations
- Glazing and doors to suit the new room
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
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
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.
Conservatory replacement questions answered
Will my neighbours in County Londonderry be involved?
If a planning application is needed, the council notifies neighbours. Where work is close to a shared boundary, we agree access and protection with them in writing.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for County Londonderry, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in County Londonderry?
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 £1,590 to £3,010 per m² including VAT, including removal.
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 County Londonderry
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.