L shaped loft conversions everything you need to know

L shaped loft conversions and everything there is to know about L shaped loft conversions. 

L shaped loft conversion is similar to the construction of dormer loft conversion with additional back back addition to the outrigger or the rear of the property. Usually this would be a bathroom as naturally usually you would have the bathroom on the first floor of the outrigger. This type of loft conversion is not possible on all types of houses it is most commonly found on those of Victorian and Edwardian era. L shaped loft conversion as a huge amount of space with either main bit of the dormer matching the height of the outrigger dormer or just below the the main dormer height this is due to planning and also layout internally as some houses have different heights in floors between main house and outrigger.


L shaped loft conversions cost from £50,000.00

L shaped loft conversion

What is a hip to gable loft conversion?


L shaped loft conversions are constructed in a way where the main house dormer and outrigger dormer is joint together forming an L shape, this is why this type of loft conversion are called L Shaped Loft Conversion. 

What are the benefits of L shaped loft conversion?


L shaped loft conversions are know for their amount of space that it offers, at most you would be able to have 2 bedrooms and separate bathroom it is dependent on the property size. None the less if you are lucky enough to own Victorian or Edwardian era property the L shaped loft conversion will be the most popular option for you.

What is L shaped loft conversion

Will i need planning permission for my hip to gable loft conversion?


Most L shaped loft conversion will fall under permitted development rules meaning you don't require planning permission. There are some exceptions flats, maisonettes, listed buildings or conservation areas may require planning permission and different rules may apply. You would also need planning if loft conversion is higher or wider then the existing roof and if you exceed 40 cubic meters on terraced house or 50 cubic meters on semi or detached house. It is recommended to simply check with the local council to confirm.

For example, you will not qualify for permitted development if:


  • The height of your dormer exceeds that of the original roof.

  • You live in a listed building or conservation area.

  • Bats live inside your loft. As a protected species, you need a special license to disturb their home.

  • Your neighbours are affected by your dormer through overlooking or overshadowing.

  • Your dormer exceeds 40 meters on a terrace house, or 50 meters on a semi-detached house or detached house.

  • Your dormer features a balcony - but Juliet balconies are fine.

  • The materials used by your dormer are out of character with the rest of your house.


If your project does falls within the permitted development, it should be made sure that the application to planning is made for Lawful Development Certificate. This will eliminate any legal issues and also helps on future sales of the house.

L shaped loft conversion London

Is my house suitable for L shaped loft conversion?


L shaped loft conversions would require outrigger to build on as well as the main dormer so they connect forming L shaped loft conversion. The houses that you would be able to have the L shaped loft conversion would be from Victorian or Edwardian era where the outriggers are already built on ground floor and first floor. 


What are the benefits of hip to gable loft conversion?


One of the main benefit of the L shaped loft conversion is the amount of space that it offers 2 rooms and a separate bathroom. Making the loft lost space most beneficial to the property and also adding value to property, you got to ask your self how much will it cost to buy a house with additional 2 bed and 1 bath in the area you live in vs adding L shaped loft conversion to your house, most people would agree to add L shaped loft conversion. 

How much does L shaped loft conversion cost in London and Hertfordshire areas?


How much does L shaped loft conversion cost in London and Hertfordshire areas is between £50,000.00 to £85,000.00 on average. 

L shaped loft conversion cost depend on many factors such as the existing condition of your existing roof, size of the roof, location of the existing staircase, are there any repairs to the existing home to be done, are chimneys in the way or they need removal or alterations, level of finishing, materials and labour needed and much more. 

How will you be sure the loft conversion does not require planning permission?


If you are not sure or want to have assurances then the best thing to do is to submit a Lawful Development Certificate application to your local council to confirm if your loft conversion meets the permitted development requirements and will determinate whether the proposed loft conversion is lawful. 

L shaped loft conversion cost

What type of spaces would hip to gable loft conversion allow me to have?


It is hugely dependent of the size of the loft, L shaped loft conversions on semi detached or detached properties up to 50 cubic meters of space where end of terrace will add 40 cubic meters. 

  1. Bedroom with separate bathroom - this is one of the most popular options and are absolutely fantastic, one of the biggest factors is that it will have a bathroom and will add another bedroom to the house. 

  2. Multi-room with separate bathroom - it is possible to have two bedrooms and separate bathroom but it is all dependent on the size of the L shaped loft conversion.

  3. L shaped loft game room and office - if you need extra room for work or gaming or play areas for children hip to gable loft conversion may be the answer, the hip to gable loft conversions offer great addition to the house and give lots extra space.

L shaped loft conversion London

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At Nuhous we are loft conversion experts a specialist loft company. We are also house extension builders a specialist in the field. With our in-house architectural design and construction team we deliver high quality loft conversions and house extensions across London and Hertfordshire areas. you can be rest assured we will start from design and planning stages to construction and finishing stages.

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