Covering Greenwich
Alongside Greenwich, we also cover Blackheath, Catford (2 miles to the south) and Peckham.
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 is included in a mansard loft conversion in Greenwich?
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 will a mansard loft conversion cost?
Typical ranges for mansard loft conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Mansard loft conversions | Guide 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 Greenwich
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?
- Council design guides often require natural slate and lead.
- Scaffolding and a temporary roof are usually needed.
What happens after I enquire?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- 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.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
Questions about a mansard loft conversion in Greenwich
Does a mansard need planning permission?
Almost always, because it changes the roof profile.
How long does a mansard take?
Around 10 to 14 weeks on site after planning approval.
Do you work in Greenwich?
Yes. Greenwich is within our coverage for mansard loft conversions, along with nearby Blackheath and Catford.
Mansard loft conversions near Greenwich
- Mansard loft conversions in Blackheath
- Mansard loft conversions in Catford
- Mansard loft conversions in Peckham
- Mansard loft conversions in Canning Town
Learn more about mansard loft conversions, or see every project we cover in Greenwich.

