Types of Loft Conversions
Loft Conversion Types We Design and Build Across London and Hertfordshire
There are five main types of loft conversions available for homes in the UK: dormer, hip to gable, L shaped, mansard and Velux. Each type suits different roof shapes, budgets and space requirements. A loft conversion is one of the most effective ways to add living space to your home, whether you need an extra bedroom, home office, playroom or en-suite bathroom.
The type of loft conversion that works best for your property depends on your existing roof shape, the amount of headroom available, planning constraints and your budget. LCCL Construction designs and builds all five types of loft conversions across London and Hertfordshire. With over 20 years of experience, more than 200 verified reviews rated 4.7 out of 5, and LABC Awards Regional Winners 2024, we can survey your property and recommend the best option for your home. Book a free consultation call to find out which type of loft conversion is right for you.
1. Dormer Loft Conversion
A dormer loft conversion is the most popular type of loft conversion in the UK. It involves building a box-shaped extension from the rear slope of the roof, with a flat roof and vertical walls that create significantly more headroom and usable floor space than the original roof line. Construction typically takes 4 to 6 weeks from scaffolding up to completion.
Dormer loft conversions create enough space for a large double bedroom with an en-suite bathroom, and often fall under permitted development rights, meaning planning permission is not usually required for most standard UK houses. This type is suitable for terraced, semi-detached and detached homes with a traditional pitched roof.
2. Hip to Gable Loft Conversion
A hip to gable loft conversion is ideal for end-of-terrace, semi-detached and detached homes where the roof slopes inward at the side (a hipped roof). The conversion straightens this sloped end wall into a vertical gable wall, creating a much larger internal floor area. Hip to gable conversions are almost always combined with a rear dormer to maximise the usable space.
This type of loft conversion has become very popular because it offers significantly more space than a dormer alone. It is also suitable for bungalows. Hip to gable conversions typically require planning permission, and construction takes around 6 to 8 weeks depending on the scope of the project.
Find out more Hip to Gable Loft Conversions
3. L Shaped Loft Conversion
An L shaped loft conversion combines two dormers arranged in an L shape, typically one across the rear of the main roof and one across the rear outrigger (the back addition found on many Victorian and Edwardian terraced houses). This design creates the largest possible loft space and is the most popular choice for mid-terrace properties in London.
L shaped loft conversions provide enough room for two bedrooms, or one very large master bedroom with a spacious en-suite bathroom and dressing area. They are particularly well suited to Victorian terraced houses with a two-storey rear outrigger. Construction typically takes 6 to 8 weeks, and planning permission is usually required due to the scale of the conversion.
4. Mansard Loft Conversion
A mansard loft conversion involves raising the party walls and replacing the existing roof with a new structure that has a flat top and steeply sloping sides (typically at 72 degrees). The near-vertical walls create the maximum amount of internal headroom and usable floor space of any loft conversion type.
Mansard conversions blend particularly well with period properties and are common on Victorian and Georgian terraced houses. They offer more headroom and natural light than other loft types, but they are also the most complex and expensive to build, typically taking 8 to 12 weeks. Mansard loft conversions always require planning permission because they significantly alter the roof shape.
5. Velux Loft Conversion
A Velux loft conversion (also called a rooflight conversion) is the simplest and most affordable type of loft conversion. It does not alter or expand the existing roof structure. Instead, Velux roof windows are installed into the existing roof slope, the floor is reinforced, insulation is added, and a staircase is built to provide access.
Because the roof shape is not changed, Velux loft conversions rarely require planning permission and are the most likely type to be approved in conservation areas. They are best suited to properties with a high roof ridge and plenty of existing headroom. Construction is typically completed in 2 to 3 weeks, making it the fastest and least disruptive loft conversion option. However, the usable floor space is more limited than other types because the sloped ceiling remains unchanged.
Which Loft Conversion Is Right for Your Home?
Not sure which type of loft conversion suits your property? Book a free consultation call and our team will assess your roof, discuss your requirements and recommend the best option for your home and budget. Call 020 8037 7332, email info@lcclconstruction.co.uk or book online.
Testimonials
Alex and his team have done a fantastic job on our loft conversion and were a pleasure to work with from start to finish. I am over the moon with the results and highly recommend them to anyone." — Katherine, Trustpilot
We used LCCL for our loft conversion after they had already done our extension. The quality of work was excellent again and we wouldn’t hesitate to use them for future projects." — Mia M, Google
Frequently Asked Questions
Q1: Which type of loft conversion is best for a terraced house?
For mid-terrace houses, an L shaped loft conversion is usually the best option because it makes use of both the main roof and the rear outrigger, creating the maximum amount of space. For end-of-terrace houses, a hip to gable combined with a rear dormer is often the most effective. A standard rear dormer is also a good option for terraced homes where budget is a priority. LCCL Construction can survey your property and recommend the type that works best for your specific roof layout.
Q2: Which type of loft conversion adds the most value to a property?
Mansard and L shaped loft conversions typically add the most value because they create the largest amount of additional living space. A well-designed loft conversion with an en-suite bathroom can add 15 to 20 percent to the value of a property, and in some London boroughs the uplift can be significantly higher. The return on investment depends on the property type, location and the quality of the conversion. All five types of loft conversion will add value if they are well designed and built to a high standard.
Q3: Do all types of loft conversion need planning permission?
No. Dormer and Velux loft conversions often fall under permitted development rights, which means planning permission is not required for most standard houses. However, hip to gable, L shaped and mansard loft conversions almost always require full planning permission because they significantly alter the roof shape. Properties in conservation areas, flats, and maisonettes will also need planning permission regardless of the type. LCCL Construction manages all planning applications as part of our design and build service.
Q4: How long does each type of loft conversion take to build?
Build times vary by type. A Velux loft conversion is the fastest at around 2 to 3 weeks. A standard rear dormer typically takes 4 to 6 weeks. Hip to gable and L shaped loft conversions take around 6 to 8 weeks. Mansard loft conversions are the most complex and usually take 8 to 12 weeks. These timescales cover the construction phase only and do not include the pre-construction design, planning and approval stages, which typically add 2 to 4 months.
Q5: Can I convert my loft if I have a low roof or limited headroom?
In most cases, yes. A dormer or mansard loft conversion can create additional headroom even where the existing roof space is limited. The minimum usable head height for a habitable room is typically 2.2 metres at the highest point. If your existing loft does not meet this, a dormer, hip to gable or mansard conversion can raise or extend the roof to achieve it. A Velux conversion is the only type that cannot increase headroom because it does not alter the roof structure. Book a free consultation and we will measure your existing roof space to confirm what is achievable.