Dormer loft conversions
A dormer builds out from the roof slope with upright walls and a roof of its own, turning the low, sloping edges of the loft into floor space with full head height.
Mansard loft conversions in Nottinghamshire
Rebuilding the back of your roof as a near-vertical wall gives you the most space any loft conversion can, with room for a large main bedroom suite or a pair of bedrooms.
- Roof change
- A steep 72° rear wall with a flat roof above
- Best for
- Terraced and period homes, and anywhere you want the most space
- Planning
- Almost always needs full planning permission
- Popular for
- Main bedroom suites, two bedrooms, or bedrooms with a bathroom
How a mansard works
A mansard replaces the rear slope of your roof with a steep wall, typically at 72 degrees, topped by an almost flat roof. The party walls are built up to the new height, so the loft becomes close to a full extra storey, with upright walls on almost every side.
Windows go into the steep rear face, as small dormers, French doors with a Juliet balcony, or roof windows. Inside, nearly the whole floor has full ceiling height.
Because it changes the shape of the roof so much, a mansard almost always needs full planning permission. We prepare the drawings for the application, then build to the approved design.
Benefits
Why choose a mansard
When a dormer won’t give you enough room, a mansard usually will.
The most space
More floor area and head height than a dormer or hip to gable, from the same roof.
Full-height rooms
Upright walls on almost every side, so the rooms feel like any other floor of the house.
A flexible layout
Room for a main bedroom with an en-suite, two bedrooms or an open-plan space.
Light at the back
French doors, Juliet balconies or roof windows can all be designed into the steep rear wall.
Key features
What your mansard conversion includes
A bigger project than a dormer, managed by one team from planning to sign-off.
- Survey and design drawings
- Drawings for your planning application
- Structural calculations and steelwork
- Party walls built up to the new height
- Steep 72-degree rear wall and flat roof
- Windows, French doors or Juliet balconies
- New staircase up to the loft
- Insulation, boarding, electrics and plumbing
- Building control approval and sign-off
Step by step
How a mansard comes together
Planning comes first, so the build starts with an approved design.
- 01
Survey and advice
We check the roof, the party walls and the space, and tell you honestly whether a mansard is the right choice.
- 02
Planning
We prepare the drawings for a full planning application, designed with your council’s guidance in mind.
- 03
Before work starts
Party wall notices are served on your neighbours, and structural calculations and building control are arranged.
- 04
Structure and roof
The steels go in, the party walls are built up, and the steep rear wall and flat roof are formed.
- 05
Inside the room
Insulation, boarding and plastering, then the electrics and plumbing are finished and the joinery fitted.
- 06
Sign-off
Building control signs the work off and the new room is handed over, ready to use.
Across Nottinghamshire
Mansards in Nottinghamshire
A mansard makes most sense where a dormer won’t give you enough room: a narrow terrace where every square metre counts, or a family that needs two bedrooms upstairs rather than one. It’s a bigger project than a dormer, so we’ll always talk through whether the extra space is worth it for your house.
Because a mansard goes through planning, the council’s view of the street matters. In a conservation area, such as the 33 in Nottingham city or The Park and Crow Hill Drive in Mansfield, materials and proportions get particular attention, and a smaller pitched dormer or roof windows can be the more sympathetic choice. We’ll tell you honestly which approach suits your home.
Planning council by councilLoft conversion projects
A few of our finished conversions and the rooms inside them.
See all our workReviews
What homeowners say
5.0
5.0 out of 5 from 31 Google reviews
5 out of 5 stars
2 bed semi loft conversion completed to give 3rd bedroom with en-suite. Headroom was tight but in the end we finished with more than expected. Very happy with the overall space gained in a small house. Any minor issues along the way were rectified and the conversion was completed in good time. The team are always polite, helpful and trustworthy!
bing17 Google review, July 2024 5 out of 5 stars
What a superb job. We were worried about having our loft conversion done in Dec but we needn’t have been. Nothing was too much trouble. The lads worked hard and we were kept up to date at all times. We love our new room and en suite and can’t praise Mark, Brin, Conan and the Mikes enough. Graham did a superb job on the roof too. Thank you all so much.
Susan C. Google review, March 2024
FAQs
Mansard loft conversions: your questions
Does a mansard need planning permission?
Almost always. It changes the shape of the roof too much to count as permitted development, so it needs a full planning application to your council. We prepare the drawings and design the mansard with the council’s guidance in mind.
Is a mansard suitable for a terraced house?
Yes. Mansards are especially popular on terraced and period homes, because they make the most of a narrow roof while keeping a tidy appearance from outside.
How is a mansard different from a dormer?
A dormer is built out from your existing roof slope, which stays in place around it. A mansard replaces the whole rear slope with a steep wall and a flat top, so it creates more space but is a bigger job and needs planning permission.
How long does a mansard take to build?
Most loft conversions take between 6 and 12 weeks, and a mansard can take longer because of the extra structural work. Planning permission comes first, and we’ll give you a detailed timeline once it’s approved.
What can I fit into a mansard conversion?
A main bedroom with an en-suite, two bedrooms, a home office or guest suite, or an open-plan living space.
Still have a question? Call 07925 891 170 or send us a message.
Thinking about mansard loft conversions?
Tell us about your house and we’ll let you know what your roof and your council allow, with a free quote.
Other loft conversions
Not sure this is the right type for your home? Compare the alternatives.
Hip to gable loft conversions
The sloping side of a hipped roof is rebuilt as an upright gable wall. With a rear dormer too, a cramped loft becomes a full-sized room.
Velux loft conversions
Roof windows set flush into the existing slope bring in daylight without changing the shape of your roof. The simplest way to convert a tall loft.
Also available
- Rear dormer loft conversionsA full-width box across the rear roof slope
- L-shaped dormer conversionsTwo linked dormers forming an L in plan view
- Pitched roof dormersA small gabled roof over each dormer window
- Shell loft conversionsStructure and weatherproofing done, fit-out left to you
These open on our main website, topmarkconversions.co.uk.
Free quote
Book your free loft conversion quote
Tell us a little about your home and what you have in mind for the space.
What happens next
- 1We read your enquiryWe go through what you’ve told us about your home and your plans.
- 2We get back to youSomeone from our team will be in touch to talk things through and answer your questions.
- 3We arrange your free quoteWe look at your loft, confirm what your roof allows and send you a detailed quote.