Covering Stevenage
Our coverage around Stevenage (SG1) also includes Hitchin (5 miles to the north-west) and Letchworth Garden City.
Homes in the East of England
Housing in the East of England ranges from post-war estates and modern developments to timber-framed and period homes in historic towns, so permitted development checks and conservation controls both feature regularly.
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.
- Planning application to local design guidance
- Slate cladding and lead-clad dormers
- En-suite, electrics and fire safety
How much does a mansard loft conversion cost in Stevenage?
Indicative costs for mansard loft conversions. London and the South East usually sit towards the top of each range.
| Mansard loft conversions | Guide price incl. VAT |
|---|---|
| Rear mansard | £65,000 to £85,000 |
| Front and rear (double) mansard | £80,000 to £110,000 |
Do you need permission for a mansard loft conversion in Stevenage?
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
Mansard conversions change the shape of the roof significantly, so they usually need planning permission in England.
What should I think about before starting?
- A mansard nearly always involves party walls on both sides of a terrace.
- Council design guides often require natural slate and lead.
From first call to completion
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
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.
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 Stevenage?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Other towns nearby
- Mansard loft conversions in Hitchin
- Mansard loft conversions in Letchworth Garden City
- Mansard loft conversions in Welwyn Garden City
- Mansard loft conversions in Harpenden
Learn more about mansard loft conversions, or see every project we cover in Stevenage.

