Mansard loft conversions in Willesden

Covering Willesden

Our coverage around Willesden (NW10) also includes Cricklewood (2 miles to the north-east) and Notting Hill.

Homes in London

Terraced houses dominate many London neighbourhoods, so most projects involve shared walls, narrow access and a party wall process. Conservation areas are widespread, and some boroughs have their own mansard and basement guidance.

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.

Planning application to local design guidance
Roof removal and new mansard frame
Slate cladding and lead-clad dormers

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

Guide prices for mansard loft conversions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.

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 Willesden?

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 affect a mansard loft conversion?

A mansard nearly always involves party walls on both sides of a terrace.
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.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

What people ask before starting

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.

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

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

Also covering

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