Mansard loft conversions · Hayes

Mansard loft conversions in Hayes

We take on mansard loft conversions in Hayes as a complete project: survey, drawings, planning or permitted development checks, building control and the construction itself.

Covering Hayes

Alongside Hayes, we also cover Southall, Heston (3 miles to the south-east) and Greenford.

Homes in London

Much of London’s housing is Victorian and Edwardian terraces, which is why side return extensions, rear dormers and mansards are so common. Many streets are in conservation areas, and several boroughs use Article 4 directions that remove some permitted development rights.

What does a mansard loft conversion involve?

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.

  • Roof removal and new mansard frame
  • Staircase, insulation and fit-out
  • En-suite, electrics and fire safety

How much should I budget for a mansard loft conversion?

Indicative costs for mansard loft conversions. London and the South East usually sit towards the top of each range.

Mansard loft conversionsGuide price incl. VAT
Rear mansard£65,000 to £85,000
Front and rear (double) mansard£80,000 to £110,000

Planning and building rules in Hayes

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.

What can affect a mansard loft conversion?

  • The roof is open for longer than with a dormer, so weather protection matters.
  • Council design guides often require natural slate and lead.

What are the steps?

  1. Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
  2. Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
  3. Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
  4. 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.

How long does a mansard take?

Around 10 to 14 weeks on site after planning approval.

Do you work in Hayes?

Yes. Hayes is within our coverage for mansard loft conversions, along with nearby Southall and Heston.

Also covering

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

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