Mansard loft conversions in Dorset

Covering Dorset

Our mansard loft conversions service in Dorset covers Bournemouth, Poole, Weymouth and Christchurch and more.

Homes in the South West

In the South West, matching local stone, render or slate is often the main design question, and conservation areas and listed buildings are common in historic towns.

What do you get with a mansard loft conversion?

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
En-suite, electrics and fire safety

What is the guide price for a mansard loft conversion in Dorset?

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

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 change the price or programme?

A mansard nearly always involves party walls on both sides of a terrace.
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.
Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

What people ask before starting

Does a mansard need planning permission?

Almost always, because it changes the roof profile.

Will I need party wall agreements?

Very likely, as the work affects the walls shared with both neighbours on a terrace.

Do you work in Dorset?

Yes. Dorset is within our coverage for mansard loft conversions, along with nearby Bournemouth and Poole.

Mansard loft conversions in nearby towns

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