Mansard loft conversions · Crawley

Mansard loft conversions in Crawley

Planning mansard loft conversions in Crawley? We design and build them for houses across West Sussex, and we fix the price for the agreed specification in writing before any building work starts.

Covering Crawley

We work in Crawley (RH11, RH77) and the places around it, including Horley, Horsham and East Grinstead.

Homes in the South East

The South East has a lot of 1930s and post-war semi-detached housing, well suited to rear extensions and hip-to-gable loft conversions, alongside period properties in conservation areas that need a more careful design.

What is included in a mansard loft conversion in Crawley?

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
  • Slate cladding and lead-clad dormers
  • 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 conversionsGuide 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 Crawley?

In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it 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 should I think about before starting?

  • 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

  1. Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
  2. We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
  3. Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
  4. Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

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.

Do you work in Crawley?

Yes. Crawley is within our coverage for mansard loft conversions, along with nearby Horley and Horsham.

Other towns nearby

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

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