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 Bury?
In Bury, 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 Bury 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 |
The main things that change the cost:
- Party wall surveyor fees
- Bathrooms and finishes
- Number of dormers and lead work
- Front, rear or both
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a mansard loft conversion in Bury?
The approval route for Bury 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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
From survey to sign-off, the job normally involves:
- Structural design and calculations
- Party wall notices to both neighbours
- New roof structure, slate or tile covering and lead work
- Insulation, electrics, plumbing and plastering
- Building control sign-off
- Planning drawings and application
How long does it take?
Allow 9 to 12 weeks on site, after planning approval. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Bury
The North West has many brick terraces and inter-war semis, where kitchen extensions and dormer loft conversions add space without moving.
Our Bury coverage includes postcode districts BL9, and we also work in nearby places such as Radcliffe, Heywood and Whitefield.
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 fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about mansard loft conversions in Bury
Can I stay at home?
Usually. The new roof is built under a temporary cover so the house stays dry.
Who approves a mansard loft conversion in Bury?
Planning matters in Bury go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Do I need party wall agreements?
Yes, mansards on terraced houses almost always involve both party walls.
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 much does a mansard loft conversion cost in Bury?
In Bury, 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.