8 London Loft Conversion Types: Which One is Perfect for Your Home In London?

Imagine transforming an unused attic into a bright, stylish living space. With the right loft conversion, that dream can become reality. In fact, UK homeowners gain an average of 30% more living space through a loft conversion—essentially creating a whole new floor without moving house.

Whether you need an extra bedroom, a dedicated home office, or simply want to boost your property’s value, choosing the right loft conversion type is crucial. At Excela Architecture London, we specialise in designing and delivering bespoke loft conversions across London, tailored to both your lifestyle and your property.

Let’s explore the eight main types of loft conversion and help you find the perfect match for your home.

1. Velux Loft Conversions (Rooflight Conversions)

Velux or rooflight loft conversions are the simplest and most cost-effective option. They involve installing roof windows that sit flush with the existing roofline.

✅ Pros:

• Minimal structural changes

• Usually fall under permitted development

• Budget-friendly option

❌ Cons:

• Limited additional space

• Requires sufficient existing headroom

Best suited for: Homes with tall roof pitches and existing attic space.

2. Dormer Loft Conversions

A dormer conversion extends vertically from the sloping roof, creating more usable floor space and headroom. This is the most popular loft conversion in London.

✅ Pros:

• Maximises usable space

• Works with most property types

• Often permitted without planning permission

❌ Cons:

• More expensive than a Velux conversion

• Alters the external appearance

Best suited for: Families needing an extra bedroom, bathroom, or home office.

3. Hip to Gable Loft Conversions

Perfect for semi-detached or detached houses with hipped roofs, a hip to gable conversion replaces the sloping end of the roof with a vertical gable wall.

✅ Pros:

• Creates significant additional space

• Can be combined with a rear dormer for maximum room

❌ Cons:

• Only suitable for certain roof types

• More complex and costly than dormers

Best suited for: Homeowners wanting a large master suite or multiple rooms.

4. Mansard Loft Conversions

A mansard conversion involves major structural changes, replacing one side of the roof with a steeply sloping wall and a flat roof. Common in terraced houses and urban areas.

✅ Pros:

• Maximises loft space

• Suitable for most property types

• Can enhance your home’s external appearance

❌ Cons:

• Almost always requires planning permission

• Higher cost due to structural work

Best suited for: Properties in central London where space is at a premium.

5. L-Shaped Dormer Conversions

Common in Victorian and Edwardian properties, L-shaped dormers combine a main rear dormer with a smaller dormer over the rear extension, forming an L-shape.

✅ Pros:

• Creates substantial space

• Can accommodate multiple rooms

• Ideal for period homes

❌ Cons:

• More costly than a standard dormer

• May require planning permission

Best suited for: Families needing several new bedrooms or a bedroom-bathroom suite.

6. Piggyback Loft Conversions

A piggyback conversion raises the existing roof to create more headroom, building up the perimeter walls before constructing a new pitched roof.

✅ Pros:

• Greatly increases headroom

• Can allow for multiple new rooms

❌ Cons:

• Requires planning permission

• High cost and longer construction time

Best suited for: Properties with very low existing loft space.

7. Side Dormer Conversions

A side dormer extends out from the side slope of the roof. This is particularly useful for homes with limited rear roof space.

✅ Pros:

• Adds valuable lateral space

• Can be combined with rear dormers

❌ Cons:

• Only suitable for certain property types

• Can affect the symmetry of semi-detached homes

Best suited for: Semi-detached and detached homes with side-facing roof slopes.

8. Pitched Dormer Conversions

A pitched dormer has a sloping roof rather than a flat top, making it more visually appealing and often favoured in conservation areas.

✅ Pros:

• Attractive design

• Suitable for conservation areas

• Adds character to your home

❌ Cons:

• Provides less usable floor space than flat dormers

• Can cost more to build

Best suited for: Homes where external appearance is a priority.

Which Loft Conversion is Right for Your Home?

The best loft conversion for your home depends on:

• Your property type (detached, semi-detached, terraced)

• Your roof structure and existing headroom

• Your budget

• Planning permission and conservation restrictions

• How you plan to use the new space

At Excela Architecture London, we assess your property and guide you through the most suitable options, balancing design vision, cost, and compliance with local regulations.

Benefits of Loft Conversions

A well-designed loft conversion offers huge benefits, including:

• Up to 30% more living space

• Up to 20% increase in property value

• A cost-effective alternative to moving house

• Potential to improve energy efficiency

• Quick construction (6–10 weeks on average)

• Versatile use (bedroom, home office, gym, studio)

• Retain garden space while gaining living space

Planning Permission for Loft Conversions

Many loft conversions in London fall under permitted development rights, but there are exceptions. You may need planning permission if:

• The loft exceeds volume allowances (40m³ for terraced, 50m³ for detached/semi-detached).

• Your home is in a conservation area.

• The roofline is being significantly altered.

• Your property is listed.

Our architects at Excela Architecture London handle planning applications, building control drawings, and compliance, ensuring your loft conversion is delivered without delays.

How to Start Your Loft Conversion Journey

Ready to unlock your loft’s potential? Here’s how to begin:

1. Assess your current loft space.

2. Research conversion options suitable for your home.

3. Set a realistic budget.

4. Check planning and building regulation requirements.

5. Consult Excela Architecture London for expert guidance.

6. Get a detailed design and build quotation.

7. Begin your transformation with confidence.

Conclusion

A loft conversion can add space, style, and significant value to your property. With so many options available—from cost-effective Velux lofts to expansive Mansard or L-shaped dormers—choosing the right type is essential.

At Excela Architecture London, we are specialists in designing and building loft conversions in London, with a proven track record of delivering projects that are functional, compliant, and tailored to our clients’ needs.

👉 Contact Excela Architecture London today to book a consultation and find out which loft conversion is perfect for your home.