Covering Washington
Our coverage around Washington (NE37, NE38) also includes Chester-le-Street (4 miles to the south-west) and Felling.
Homes in the North East
In the North East, terraces, semis and bungalows all offer room to extend, with stone-built villages and conservation areas in parts of County Durham and Northumberland.
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
How much should I budget for a mansard loft conversion?
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 |
What approvals does a mansard loft conversion need in England?
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 should Washington homeowners check first?
- A mansard nearly always involves party walls on both sides of a terrace.
- Council design guides often require natural slate and lead.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- 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 Washington
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.
Does a mansard need planning permission?
Almost always, because it changes the roof profile.
Can you visit a house in Washington 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.
Other towns nearby
- Mansard loft conversions in Chester-le-Street
- Mansard loft conversions in Felling
- Mansard loft conversions in Houghton-le-Spring
- Mansard loft conversions in Hebburn
Learn more about mansard loft conversions, or see every project we cover in Washington.

