Covering Derry
We work in Derry (BT47) and the places around it, including Strabane, Limavady and Coleraine.
Homes in County Londonderry
Northern Ireland has a high proportion of detached houses and bungalows outside the cities, which often suit side extensions, rear extensions and upward extensions.
What is a mansard loft conversion?
Mansards are a bigger structural job than other conversions because the roof is largely rebuilt. They normally need planning permission, and many councils have design guides setting the angle, materials and window style. We prepare the design to those guides and build in slate, lead and timber or approved alternatives.
- Planning application to local design guidance
- Roof removal and new mansard frame
- Slate cladding and lead-clad dormers
What will a mansard loft conversion cost?
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 |
Planning and building rules in Derry
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.
This needs full planning permission from the council in Northern Ireland, plus building control approval.
What should I think about before starting?
- The roof is open for longer than with a dormer, so weather protection matters.
- Scaffolding and a temporary roof are usually needed.
From first call to completion
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- 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.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
How much does a mansard loft conversion cost?
Typically £65,000 to £110,000 including VAT, depending on whether one or both roof slopes are rebuilt.
How long does a mansard take?
Around 10 to 14 weeks on site after planning approval.
Can you visit a house in Derry to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Mansard loft conversions in nearby towns
- Mansard loft conversions in Strabane
- Mansard loft conversions in Limavady
- Mansard loft conversions in Coleraine
- Mansard loft conversions in Omagh
Learn more about mansard loft conversions, or see every project we cover in Derry.