Mansard loft conversions in Richmond

Covering Richmond

Our coverage around Richmond (TW9) also includes Isleworth, Hounslow and Barnes.

Homes in London

London projects often mean working on period terraces with neighbours on both sides, tight access through the house and conservation area controls, so careful planning and party wall work matter as much as the build.

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
Staircase, insulation and fit-out
En-suite, electrics and fire safety

What will a mansard loft conversion cost?

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

How is a mansard loft conversion approved in Richmond?

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. Many councils publish guidance on mansard design.

What can change the price or programme?

Council design guides often require natural slate and lead.
Scaffolding and a temporary roof are usually needed.

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.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
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.

Mansard loft conversions: common questions

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.

How do I get a price for mansard loft conversions in Richmond?

Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.

Other towns nearby

Learn more about mansard loft conversions, or see every project we cover in Richmond.