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.
In Larne, as anywhere in County Antrim, the price of a loft conversion is driven mainly by size, materials and access. Across Northern Ireland our guide sits at £26,000–£56,000 with VAT, but restricted parking, a narrow side passage or extra preparation can move the figure either way. That is why every price we give follows a visit to the house.
- Guide price
- £26,000–£56,000 inc VAT
- Time on site
- 6–10 weeks on site
- Postcodes
- BT40
- Planning rules
- Northern Ireland
- Local area
- County Antrim
- Survey
- Free, with a written quote
What should you budget for a loft conversion in Larne?
Prices for a loft conversion vary from house to house, but in Larne most projects fall within £26,000–£56,000 including VAT. That reflects costs in Northern Ireland, about 14% below the national guide. Treat the table as a budgeting aid; the written figure follows a survey we carry out for free.
| Type of job | What it usually involves | Guide in Larne |
|---|---|---|
| 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 |
Expect these to shape the final quote:
- 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
- Staircase layout, fire doors and the level of finishes
Scope of the work
- Structural calculations and steel beams where needed
- New floor joists strong enough for a habitable room
- 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
Building in Larne
Belfast has long rows of red-brick Victorian terraces, Edwardian villas in the north and south of the city and large post-war estates, while towns such as Ballymena, Antrim, Larne and Carrickfergus mix terraces, semis and newer developments. Dark basalt appears in older rural buildings, and pebbledash or roughcast is a very common finish.
Terraces suit loft conversions and rear extensions, and many need window and roof renewal. Pebbledashed homes commonly need re-rendering, and detached rural houses often take extensions, porches and driveways.
That mix of housing shapes how we approach a loft conversion in Larne: the age and construction of your home affect the materials, the method and, in the end, the price.
Planning and building rules in Larne
As Larne is in Northern Ireland, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a quote.
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.
From survey to handover
We look at the job
We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a loft conversion so the price reflects your home.
Written quote
You get the price in writing, itemised so you can see where the money goes. As long as the specification stays the same, that is the price you pay for a loft conversion.
Booking the work
We handle the paperwork side: checking whether planning permission or building control approval is needed, submitting applications where they are, and scheduling the trades and materials around your dates.
The work itself
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Questions about a loft conversion in Larne
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.
Can you combine a loft conversion with other work?
Yes. Because we manage several trades under one contract, we can plan a loft conversion alongside other work on your Larne home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same 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.
What fire safety measures does a loft conversion need?
A loft conversion needs a safe way out in a fire, because the new room is high above the ground. This usually means a protected stair route down to an exit, with fire doors onto the stairway, mains-linked smoke alarms on each floor and sometimes an escape window. The exact approach depends on your house layout. Building control checks these measures before signing off the work.
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.
Nearby towns
Addresses in BT40 are all covered for Larne, along with Carrickfergus, Newtownabbey and Bangor, County Down close by. Give us your postcode when you get in touch and we will confirm the details.

