Covering Gosport
Our coverage around Gosport (PO12) also includes Portsmouth, Fareham and Ryde.
Homes in the South East
Housing across the South East mixes inter-war semis, post-war estates and older cottages in villages and market towns, so rear and side extensions, hip-to-gable lofts and garage conversions all come up regularly.
What does a mansard loft conversion involve?
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.
- Roof removal and new mansard frame
- Slate cladding and lead-clad dormers
- Staircase, insulation and fit-out
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 |
What approvals does a mansard loft conversion need in England?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.
Mansard conversions change the shape of the roof significantly, so they usually need planning permission in England.
What can affect a mansard loft conversion?
- A mansard nearly always involves party walls on both sides of a terrace.
- The roof is open for longer than with a dormer, so weather protection matters.
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.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Your questions answered
How long does a mansard take?
Around 10 to 14 weeks on site after planning approval.
Will I need party wall agreements?
Very likely, as the work affects the walls shared with both neighbours on a terrace.
Who deals with the council for a project in Gosport?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Also covering
- Mansard loft conversions in Portsmouth
- Mansard loft conversions in Fareham
- Mansard loft conversions in Ryde
- Mansard loft conversions in Waterlooville
Learn more about mansard loft conversions, or see every project we cover in Gosport.

