Conservatory replacement extensions across Lisburn
Planning a conservatory replacement in Lisburn? 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 LisburnFrom £17,000 inc VAT
- PlanningNI permitted development (rear 3–4 m) or planning
- Build time8–14 weeks on site
- Postcode districtsBT10, BT11, BT17, BT27, BT28

Who a conservatory replacement suits
- Older uPVC conservatories near the end of their life
- Homes where the conservatory sits unused
- Conservatories that are too hot or too cold
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.
Guide prices for Lisburn
These guide figures apply our Northern Ireland adjustment (×0.86) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Lisburn: £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.
Extensions in and around Lisburn
Across BT10, BT11, BT17, BT27, BT28, we can visit, measure and advise. Nearby, we also take on projects in Belfast (7 miles), Castlereagh (7 miles), Newtownabbey (11 miles), Antrim (15 miles).
Northern Ireland's housing ranges from city terraces to large numbers of detached houses and bungalows on rural plots, many in render, where single-storey extensions fit easily.
Planning and approvals in Lisburn
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.
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.
Building close to a public sewer needs the agreement of NI Water, which we check during design.
Applications are decided by your council, which handles local planning in Northern Ireland.
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
We visit your Lisburn 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
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Lisburn
Do I need building regulations approval in Lisburn?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a conservatory replacement take to build in Lisburn?
On site, typically 8 to 14 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Lisburn, 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.
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.
Book a free site visit in Lisburn
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.