What is a mansard loft conversion?
A mansard loft conversion rebuilds the roof with a nearly vertical slope (about 72 degrees) and a flat top, effectively adding a new storey. Small dormer windows sit within the steep slope. Mansards are common on period terraces in towns and cities.
How much does a mansard loft conversion cost in Stockport?
In Stockport, a mansard loft conversion typically costs £61,000–£89,500 for a typical rear mansard, including VAT at 20% (standard rate). Building costs in the North West run about 6% below the UK average, and the figures for Stockport are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rear mansard | £61,000–£89,500 |
| Higher specification | £89,500–£112,000 |
Your quote will depend mainly on:
- Bathrooms and finishes
- Scaffolding on busy streets
- Roof covering: natural slate costs more
- Party wall surveyor fees
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a mansard loft conversion in Stockport?
The approval route for Stockport is set by planning law in England. In England a mansard almost always needs planning permission because it changes the roof shape. Many councils publish design guidance for mansards on terraced streets, and some streets are more likely to be approved where neighbours already have one.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
We check this for your address before design work starts, so there are no surprises later.
What we handle
Handled as part of most mansard loft conversions:
- Insulation, electrics, plumbing and plastering
- Structural design and calculations
- New roof structure, slate or tile covering and lead work
- Dormer windows
- Planning drawings and application
- Building control sign-off
How long does it take?
Expect 9 to 12 weeks on site, after planning approval. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Stockport
Terraced streets across the North West often suit rear dormers and single-storey kitchen extensions.
Projects in Stockport (SK1 and SK3) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about mansard loft conversions in Stockport
Why choose a mansard over a dormer?
A mansard gives more usable floor space and a neater appearance from the street, but costs more and needs planning permission.
How long does a mansard loft conversion take in Stockport?
Typically 9 to 12 weeks on site, after planning approval. Design and approvals beforehand usually take 3 to 4 months.
How much does a mansard loft conversion cost in Stockport?
In Stockport, a mansard loft conversion typically costs £61,000–£89,500 for a typical rear mansard, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Does a mansard need planning permission?
Almost always, because it changes the roof shape. Councils assess it against local design guidance.
Do I need party wall agreements?
Yes, mansards on terraced houses almost always involve both party walls.