Mansard loft conversions in Northamptonshire

Covering Northamptonshire

Our coverage across Northamptonshire includes Northampton, Corby, Kettering and Wellingborough.

Homes in the East Midlands

Housing in the East Midlands includes Victorian terraces, inter-war semis and newer estates, with stone-built villages in some areas where conservation controls apply.

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
Structural design and party wall process
Staircase, insulation and fit-out

How much should I budget for a mansard loft conversion?

What mansard loft conversions typically cost. These are guide ranges; the written quote for your house replaces them.

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 Northamptonshire?

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

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.
Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

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.

Why choose a mansard over a dormer?

A mansard gives more usable space and often fits a street better where neighbours already have one.

Can you visit a house in Northamptonshire 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 near Northamptonshire

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