Opening up your loft to create new accommodation is an exciting option – with many different types of floor plan and design possible. An L-shaped loft conversion is a design which can create the largest amount of space, particularly when additional headroom is required. This larger space gives plenty of configuration options, including multiple rooms.

What is an L-Shaped Loft Conversion?

An L-shaped conversion involves an L-shaped dormer window (dormers are the roof windows which extend vertically from the slope of a roof).

With L-shaped loft conversions, two dormers connect into a corner. One end of the dormer, usually the larger end, is built into the main roof. The other end of the dormer is built into the roof of an existing rear extension.

L-Shaped Loft Conversion

It’s possible to create a roof space which closely replicates the space and design of the first floor. A standard loft conversion on a Victorian or Edwardian terraced property would generally bring a single room, with perhaps a very snug en-suite or study nook. Alternatively, an L-shaped conversion can create an additional room of up to 2m x 2m into the overall design. Why not try our loft conversion calculator to get a rough estimate on price.

Is your property suited to an L-Shaped Loft Conversion?

Because they rely on a rear extension to allow the L-shaped floor plan, L-shaped conversions are only possible on certain types of property.

Victorian and Edwardian terrace and end-of-terrace houses with a two-storey rear extension usually offer a good option for this type of loft conversion, as most of these have the addition to the rear of the house which creates the L-shaped roof.

The benefits of an L-Shaped Loft Conversion

The fact that these original back extensions on terraced homes were often constructed to provide a ground floor kitchen and first-floor bathroom means that the rear roof area is a popular choice for an en-suite bathroom or shower room. Existing plumbing, such as soil pipe, can be tapped into in a cost-effective way.

L-Shaped Loft Conversion en-suite

L-shaped loft conversions can also be an ideal way to gain additional space in a property which has limited garden space, as going up into the loft means not having to lose vital garden space to a ground floor extension.

Do you need planning permission for an L-Shaped Loft Conversion?

The majority of L-shaped dormer loft conversions do not require planning permission as they usually fall within the 40/50 cubic metres which is allowed under UK Permitted Development rules (40 cubic metres is the maximum allowed for terraced properties / 50 cubic metres for semi-detached and detached homes).

However, as all local authority planning policies vary, it is essential to double-check with the local planning office and your loft professional, as issues such as being in a conservation area, the proposed side of the conversion facing the road or other properties can be factors which could make an application for planning permission necessary.

Whether or not planning permission is required, building regulations will need to be adhered to, so the conversion will need to be completed in compliance with regulations and certification for compliance obtained once the works have been completed. Again, the local planning office and your loft professional should be able to offer complete guidance on these processes.

Deciding on your L-Shaped Loft Conversion floorplan

Once it’s been established that the roof space is suitable for conversion, then the real decision-making about design and potential floorplan begins. All of those design options – including multiple rooms, size, fixtures, fittings and stairway – come into consideration depending on the budget available, the type of accommodation needed and any other features required, such as a Juliet balcony.

For a terraced or end-of-terrace property suited to an L-shaped dormer conversion, the standard design involves:

  • A larger, almost flat roof dormer built across the width of the rear of the main roof. This dormer extends around and over the additional rear roof area.
  • An additional almost flat roof dormer built into the rear roof area. This aspect does not generally extend across the whole width of the rear roof as this would take the conversion beyond the 40 cubic metres allowed under permitted development.
  • Subject to planning regulations, the design could be swapped around as required, so the full width of the rear roof could be used for the majority of the dormer and the smaller end of the dormer built into the main roof.
  • Velux windows can be added to allow additional light across the extension as required.
  • The roof aspects of the dormer generally appear flat but mostly incorporate a gentle slope which allows water to run off rather than collect and deteriorate the roof area.

L-Shaped Loft Conversion yoga room

Having an additional room as part of the plan gives plenty of options on how to use the accommodation:

  • A master bedroom with en-suite and dressing room.
  • Children’s bedroom or playroom with full-sized bathroom.
  • Teenage or adult child’s suite with en-suite and study.
  • Yoga studio with shower facilities.

Once you get this far with the idea, it’s easy to struggle with choice-stress or to find it hard to identify a design which matches the ‘ideal’ you’re looking to achieve. So, at this stage, it’s a good idea to arrange a free site survey and quote from a professional loft company, so you have a realistic starting point on what can be achieved for the budget available.

There really are no limits on how the extended L-shaped conversion can be used to create accommodation which fits in with your household, lifestyle and budget.

How long does an L-Shaped Loft Conversion take?

As with any loft conversion, the time it takes will depend on many factors – including whether you’re using a one-man building company or a specialist loft company.

Using a professional team ensures the planning and construction work takes place in compliance with planning requirements and is completed to a professional standard. It also means that a dedicated team work on the loft conversion, which means the work takes place more quickly and efficiently.

As multiple rooms are being constructed, this type of conversion could take between 6 to 12 weeks, depending on configuration and other factors.

To discuss your L-shaped loft conversion ideas and plans, contact us today or request a free, no-obligation quote online.