Covering Great Sankey
We work in Great Sankey (WA5) and the places around it, including Warrington, Newton-le-Willows and Widnes.
Homes in the North West
The North West has long rows of Victorian terraced houses in its towns and cities, alongside inter-war semis and post-war estates, so rear extensions, dormer lofts and kitchen extensions are common projects.
What goes into a mansard loft conversion?
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.
- Structural design and party wall process
- Staircase, insulation and fit-out
- En-suite, electrics and fire safety
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 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 Great Sankey
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.
What should I think about before starting?
- A mansard nearly always involves party walls on both sides of a terrace.
- Council design guides often require natural slate and lead.
From first call to completion
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- 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.
Your questions answered
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 Great Sankey?
Yes. Great Sankey is within our coverage for mansard loft conversions, along with nearby Warrington and Newton-le-Willows.
Mansard loft conversions in nearby towns
- Mansard loft conversions in Warrington
- Mansard loft conversions in Newton-le-Willows
- Mansard loft conversions in Widnes
- Mansard loft conversions in Runcorn
Learn more about mansard loft conversions, or see every project we cover in Great Sankey.

