Covering Lisburn
Alongside Lisburn, we also cover Belfast, Newtownabbey (11 miles to the north-east) 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 does a mansard loft conversion involve?
A mansard loft conversion replaces one or both slopes of a roof with a near-vertical wall, typically at 70 degrees, with small dormer windows set into it. It creates almost a full extra storey and is common on terraced houses in towns and cities, particularly in London.
- Roof removal and new mansard frame
- Slate cladding and lead-clad dormers
- Staircase, insulation and fit-out
How much does a mansard loft conversion cost in Lisburn?
Typical ranges for mansard loft conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Mansard loft conversions | Guide price incl. VAT |
|---|---|
| Rear mansard | £65,000 to £85,000 |
| Front and rear (double) mansard | £80,000 to £110,000 |
What approvals does a mansard loft conversion need in Northern Ireland?
Northern Ireland projects need planning clearance and building control approval from the local council. We prepare the applications and agree any work near neighbouring property directly with the neighbours.
This needs full planning permission from the council in Northern Ireland, plus building control approval.
What can change the price or programme?
- The roof is open for longer than with a dormer, so weather protection matters.
- Council design guides often require natural slate and lead.
What happens after I enquire?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- 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 mansard loft conversion in Lisburn
Does a mansard need planning permission?
Almost always, because it changes the roof profile.
Why choose a mansard over a dormer?
A mansard gives more usable space and often fits a street better where neighbours already have one.
Do you work in Lisburn?
Yes. Lisburn is within our coverage for mansard loft conversions, along with nearby Belfast and Newtownabbey.
Other towns nearby
- Mansard loft conversions in Belfast
- Mansard loft conversions in Newtownabbey
- Mansard loft conversions in Holywood
- Mansard loft conversions in Comber
Learn more about mansard loft conversions, or see every project we cover in Lisburn.

