Covering Lisburn
Our coverage around Lisburn (BT27, BT28) also includes Belfast, Newtownabbey and Holywood.
Homes in County Antrim
Across Northern Ireland you find city terraces, suburban semis and rural bungalows and farmhouses, so the right approach depends on the plot and the planning history.
What goes into a dormer loft conversion?
A dormer loft conversion builds a box-shaped extension out from the rear slope of the roof, creating vertical walls and full head height across most of the new floor. It is the most popular type of loft conversion because it gives the most usable space for the cost.
- Dormer frame, roof covering and cladding
- Staircase, insulation and plasterboard
- En-suite, electrics and fire-protected escape route
How much does a dormer loft conversion cost in Lisburn?
Use these ranges to budget for dormer loft conversions; the survey turns them into a fixed price for the agreed specification.
| Dormer loft conversions | Guide price incl. VAT |
|---|---|
| Rear dormer, bedroom only | £50,000 to £65,000 |
| Full-width dormer with en-suite | £60,000 to £80,000 |
| L-shaped dormer (over rear outrigger) | £65,000 to £90,000 |
Do you need permission for a dormer loft conversion in Lisburn?
Projects in Northern Ireland need planning clearance from one of the eleven councils and building control approval, also from the council. The Party Wall etc. Act does not extend to Northern Ireland, so work near neighbours is agreed directly and documented carefully.
In Northern Ireland, roof enlargements such as dormers often need planning permission depending on size and position. Building control approval is needed for every loft conversion.
What can change the price or programme?
- A flat dormer roof needs proper falls and a quality membrane.
- L-shaped dormers are common on Victorian terraces with a rear outrigger.
What happens after I enquire?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Questions about a dormer loft conversion in Lisburn
How much does a dormer loft conversion cost?
Typically £50,000 to £80,000 including VAT, and up to around £90,000 for an L-shaped dormer.
What cladding can a dormer have?
Tile-hanging to match the roof, render, slate, timber or zinc, depending on the house and any planning conditions.
How do I get a price for dormer loft conversions in Lisburn?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Dormer loft conversions in nearby towns
- Dormer loft conversions in Belfast
- Dormer loft conversions in Newtownabbey
- Dormer loft conversions in Holywood
- Dormer loft conversions in Comber
Learn more about dormer loft conversions, or see every project we cover in Lisburn.

