Rear dormer loft conversions
A box dormer across the back slope, with upright walls and a flat roof, for the biggest room a single dormer can give. The street side of the roof doesn’t change.
L-shaped dormer loft conversions in Nottingham
Built over the main roof and the rear outrigger together, an L-shaped dormer turns the two awkward roofs of a Nottingham terrace into a top floor with room for a bedroom and a bathroom.
- Roof change
- Two linked dormers forming an L in plan view
- Best for
- Victorian and Edwardian terraces with a rear outrigger
- Space
- Much more than a single dormer, often enough for two rooms
- Planning
- Usually permitted development; an application in a conservation area
How an L-shaped dormer works
Many terraced houses have a narrower back section, the outrigger, with a lower roof of its own. An L-shaped dormer builds one dormer off the rear slope of the main roof and a second along the outrigger roof, joined at the corner so that from above they form an L.
Using both roofs gives a far bigger floor than one dormer could, and it can be divided into separate spaces: a bedroom with an en-suite, say, or a bedroom and a study.
We plan the layout around the new staircase and the shape of your house, arrange the structural engineer’s calculations and building control, and build it through to the finished rooms.
Benefits
What an L-shaped dormer gives a terrace
The most usable space you can usually get from a terraced roof without rebuilding it.
Two roofs, one floor
The main roof and the outrigger are joined into a single top floor instead of two cramped spaces.
Room for a bathroom
The extra floor area usually leaves space for an en-suite or shower room beside the bedroom.
Light from two sides
Dormer windows on both wings, plus roof windows if you want them, keep the whole floor bright.
The street view stays the same
Everything is built at the back, so the front of your terrace looks as it always has.
Key features
What your L-shaped dormer includes
One quote for the whole build, from the survey to the sign-off.
- Survey of both roofs and the outrigger
- Layout drawings for the new floor
- Permitted development check or planning drawings
- Structural engineer’s calculations and steels
- Both dormers framed, roofed and clad
- Dormer windows and any roof windows
- A new staircase up from the landing
- Insulation, plasterboard, electrics and plumbing
- Building control approval and completion
Step by step
How we build an L-shaped dormer
The structure goes in first, then both dormers are made weathertight before any work starts inside.
- 01
Survey
We measure the main roof and the outrigger, check the structure and work out where the stairs can rise.
- 02
Drawings and approvals
Plans for both wings, a permitted development check or planning drawings, calculations and building control.
- 03
Steels and stairs
The steels and the new floor go in, followed by the staircase from the landing below.
- 04
Both dormers
The main dormer and the outrigger dormer are framed, roofed and clad, and the windows fitted.
- 05
Fitting out
The room is insulated, boarded and plastered, then the electrics, plumbing and joinery are finished off.
- 06
Handover
Building control inspects and signs off the work, and the new floor is handed over to you.
In Nottingham
L-shaped dormers on Nottingham terraces
The rows of Victorian and Edwardian terraces built around Nottingham’s lace and hosiery trades are where L-shaped dormers come into their own. Where the house has a rear outrigger, building over both roofs usually gives the most usable space; where it doesn’t, a single rear dormer is the normal choice instead.
Many terraces can take an L-shaped dormer under permitted development. If yours is in one of the city’s 33 conservation areas, it will need a planning application, and Nottingham City Council’s design guide then looks for dormers that line up with the windows below and avoids flat roofs unless the case officer agrees.
Planning in NottinghamLoft 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
Mark and the team were brilliant! They completed my loft conversion, creating a third bedroom in my terraced house, to an excellent standard. From the start of the project they kept me upto date and nothing was too much trouble. Really lovely guys and I couldn’t recommend them highly enough. Thanks!
Claire O. Google review, September 2024 5 out of 5 stars
If you’re looking for a builder to do a loft conversion- stop looking right now. You’ve found him. Mark and his team have been excellent right from the start. From giving us a quote, he was able to quell all of our concerns and give us the information that we required in a succinct and predictable way. He was readily accessible for any questions and was able to give us the required information well in advance of any changes to any plans. When he started the work, he was always on time and they were always very polite and friendly. They also used our toilet during the works, which I am happy to say they always left the toilet in a clean manner. Whenever they worked within the house, they were always respectful and put down the necessary protection to limit any damage to our existing carpet and furniture. At the end of each day, they always cleaned up after themselves and left the place in a clean manner. They were very efficient with their work too. They were able to do our loft conversion (structure up) within 5 weeks, which is astounding! It was also during a very wet season and they took care not to have any leakage or water damage to any of our house. They gave us enough time to make decisions so that everything could be put in place without delay. All of the contractors that they work with have also been very professional and do their work to a high standard. We were then able to use these same contractors for any additional jobs we had around the house (at our own cost) for convenience. If we did come across anything that wasn’t quite right- Mark or one of his team were quick to respond to any of our concerns. Mark and his team are top notch and extremely professional. It was an absolute pleasure working with them and I would highly recommend them for any work being done.
Demi W. Google review, April 2024
FAQs
L-shaped dormer loft conversions: your questions
What is an outrigger, and why does it matter?
It’s the narrower part at the back of many terraced houses, usually holding the kitchen or bathroom, with a lower roof of its own. An L-shaped dormer builds over that roof as well as the main one, which is why it gives so much more space.
Can I keep living at home during an L-shaped dormer build?
In most cases, yes. Nearly all the work happens in the roof, and we keep the site safe and tidy while we’re there.
Does an L-shaped dormer cost more than a rear dormer?
Usually, yes, because it involves more structural work and creates a much larger space. Your quote is detailed, so you can see where the cost goes.
Will I need planning permission in Nottingham?
Often not, if the dormers stay within the national size limits and your home isn’t in a conservation area. Inside one of the city’s 33 conservation areas, you will. We check your address before we start the design.
Still have a question? Call 07925 891 170 or send us a message.
Thinking about l-shaped dormer 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.
Pitched dormer loft conversions
A smaller dormer under its own sloping roof, matched to the main roof. It often suits Nottingham’s period houses and conservation areas better than a flat-roofed box.
Also available
- Hip to gable conversionsThe sloping hip rebuilt as a vertical gable wall
- Dormer loft conversionsA box extension built out from the roof slope
- Mansard loft extensionsA steep 72° rear wall with a flat roof above
- Velux conversionsRoof windows set flush into the existing slope
- Shell loft conversionsStructure and weatherproofing done, fit-out left to you
These open on our main website, topmarkconversions.co.uk.
Free quote
Start your Nottingham loft conversion
A few details about the house and what you’d like from the loft are all we need to begin.
What happens next
- 1We read it throughSomeone from our team looks at what you’ve sent about the house and your plans.
- 2We call you backWe talk through what you have in mind and answer your first questions.
- 3We visit and quoteWe survey the loft, check your street’s planning position and send a detailed, free quote.