A loft conversion turns unused roof space into a habitable room such as a bedroom, bathroom or office, with a proper staircase, insulation, fire protection and natural light from rooflights or a dormer.
Cost is usually the first question about a loft conversion, so here is the guide for Northern Ireland: £26,000–£56,000 including VAT. We cover the whole of County Down, with Bangor, County Down, Castlereagh, Newtownards and Newry among the main centres. Because each UK nation sets its own rules, we check the requirements in Northern Ireland for your property, then put a firm price on paper following a free survey.
- Guide price
- £26,000–£56,000 inc VAT
- Time on site
- 6–10 weeks on site
- Planning rules
- Northern Ireland
- Price level
- About 14% below the national guide
- Towns listed
- 5
- Survey
- Free, with a written quote
Loft conversions prices in County Down
No two jobs cost exactly the same, but the ranges below give a fair picture of a loft conversion in County Down. Pricing for Northern Ireland runs about 14% below the national guide, and the overall guide is £26,000–£56,000 with VAT included. We'll confirm your figure after surveying the property for free.
| Type of job | What it usually involves | Guide in County Down |
|---|---|---|
| Rooflight conversion | Rooflights in the existing slope, a new floor, staircase and insulation, where head height already works. | £17,000–£30,000 |
| Dormer conversion | A rear dormer adding headroom and floor space, often with a bedroom and shower room. | £27,500–£52,000 |
| Hip-to-gable or mansard | Larger structural changes to the roof for the maximum usable space. | £43,000–£73,000 |
The main things that change the figure:
- Conversion type: rooflight, dormer, hip-to-gable or mansard
- Floor area, existing head height and roof structure
- Steelwork and any strengthening of walls below
- Adding a shower room or en-suite in the roof
What do you get?
- New floor joists strong enough for a habitable room
- Dormer, hip-to-gable or rooflight structure as agreed
- Staircase designed to fit your landing and meet regulations
- Insulation to walls, roof slope and floor
- Electrics, heating and plumbing by qualified trades, with certificates
- Plastering, internal doors and building control sign-off
Housing across County Down
County Down takes in suburbs of Belfast, Bangor and Holywood with Victorian and Edwardian villas, and Newry, Downpatrick and Banbridge with older town centres and newer estates. Mourne granite appears in buildings around the mountains, and detached rural homes and bungalows are common across the county, often rendered or pebbledashed.
Villas and semis suit kitchen extensions, loft conversions and garden landscaping. Rural detached homes commonly take extensions and driveways, and rendered houses often need re-rendering, roofline renewal and window replacement.
Coastal areas such as the Ards Peninsula face salt and wind, and the Mournes bring heavier rain and colder conditions.
Do you need permission in County Down?
Homes in County Down come under the regulations for Northern Ireland, summarised below. We don't rely on general rules alone: we confirm the position for your address with the council before a quote goes out.
In Northern Ireland, loft conversions can be permitted development, with dormers controlled mainly by their position and set-backs rather than a volume limit; front-facing dormers and work in conservation areas usually need planning permission.
Building control approval under the Building Regulations (Northern Ireland) is needed. There is no Party Wall Act in Northern Ireland.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
The four stages
Survey and measure
First, someone visits your home in County Down to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
Quote in writing
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
Booking the work
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a loft conversion are in place before the first day on site.
Finish and handover
The job proceeds in the order set out in the programme, with dust and debris kept under control. Finally we tidy away, inspect the work together and pass the finished project over to you with its paperwork.
How we work
Questions about a loft conversion in County Down
Where will the new staircase go?
The new staircase usually sits above the existing stairs, rising from the landing so it uses space that is already circulation. Sometimes it needs to come from a small bedroom or box room, which reduces that room's size. Building regulations set rules on headroom, step size and handrails, with some flexibility for lofts. We look at options at the survey and show you how each affects the floor below.
How much does a loft conversion cost?
A typical dormer loft conversion on a 3-bed semi costs £26,000–£56,000. A simple rooflight conversion costs less, while hip-to-gable and mansard conversions cost more because they change the roof structure. As a rough guide, allow around £800–£1,700 per square metre of new floor plus fixed costs for the staircase, steels and fees. Adding a shower room is the most common extra. We confirm a fixed price after surveying your loft.
How much will a loft conversion cost in County Down?
As a guide, expect to pay £26,000–£56,000 including VAT for a loft conversion in County Down. That range is adjusted for Northern Ireland, which runs about 14% below the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a loft conversion, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
Do I need planning permission for a loft conversion?
Whether a loft conversion needs planning permission depends on its size and design, your home's location, whether it is listed or in a conservation area, and which UK nation you live in. In England, many conversions fall under permitted development if the added volume is within 40m³ for terraced houses or 50m³ for other houses and nothing extends beyond the front roof slope. We check what applies before quoting.
Towns in County Down
Looking for a loft conversion somewhere in County Down? Start with the towns below; each links to a page with pricing for your region and coverage details.