What is the Difference Between a Velux, Dormer and Hip to Gable Loft Conversion?
What is the Difference Between a Velux, Dormer and Hip to Gable Loft Conversion?
This comprehensive guide reveals everything homeowners in Solihull and Warwick need to know about the three main types of loft conversion in 2025.
Based on verified UK building standards and our extensive experience across the area, we examine what makes each conversion type different, which suits different properties, and how to choose the right one for your home and budget.
Key topics covered:
- What each type of loft conversion actually is and how it works
- Which properties suit each conversion type
- Cost differences between Velux, dormer, and hip to gable conversions
- How much space each type creates
- Planning permission requirements for each
- Which conversion adds the most value to your property
- Common combinations and what works best in Solihull and Warwick
Understanding Loft Conversion Types: More Than Just Different Windows
When you start looking into loft conversions, you’ll quickly come across three main types: Velux, dormer, and hip to gable. These aren’t just different ways of adding windows. They’re fundamentally different approaches to creating usable space in your loft, and choosing the wrong one for your property can be an expensive mistake.
The key difference is how much they change your existing roof structure and how much usable space they create.
What is a Velux Loft Conversion?
The Basics
A Velux loft conversion, also known as a rooflight or skylight conversion, is the simplest type. The existing roof structure stays exactly as it is. You’re not changing the shape or extending anything. Instead, you’re fitting windows into the slope of your existing roof to bring in light and make the space habitable.
The term “Velux” comes from the brand name that dominates the roof window market, much like “Hoover” became synonymous with vacuum cleaners. You can use other manufacturers’ windows, but everyone calls this type of conversion a Velux conversion regardless.
How It Works
The roof structure remains completely unchanged. Windows are fitted flush into the existing roof slope, typically sitting no more than 150mm above the roof plane to comply with permitted development. The loft space is insulated, a floor is installed, a staircase is added, and electrics and heating are fitted. That’s it.
Because you’re working within the existing space rather than creating new space, this only works if your loft already has sufficient headroom. You need at least 2.2 metres from floor to the highest point of the roof to meet building regulations, though 2.4 metres is more realistic for a comfortable space.
Which Properties Suit Velux Conversions
Velux conversions work best on properties that already have generous loft spaces with good headroom. Older Victorian and Edwardian houses around Solihull and Warwick often have substantial roof spaces that make excellent Velux conversions. Properties with steep roof pitches between 15 and 90 degrees are suitable.
They don’t work well on properties with shallow roof pitches or limited headroom, because you can’t create more height without changing the roof structure.
Cost
Velux conversions are the most cost-effective option because they involve the least structural work. Costs start from around £28,000 to £35,000 for a basic conversion, rising to £45,000 to £55,000 for higher specifications with multiple windows and ensuite bathrooms.
Value Added
Research shows that Velux conversions typically add 5% to 10% to property value. For a house in Solihull worth £380,000, that’s roughly £19,000 to £38,000 added value for an investment of £28,000 to £55,000.
What is a Dormer Loft Conversion?
The Basics
A dormer loft conversion involves extending your existing roof structure outwards to create a box-shaped projection. This creates vertical walls where previously you only had sloping roof, which dramatically increases both headroom and usable floor space.
The dormer projects vertically from the plane of your existing roof slope. It has its own walls, windows, and roof, creating what looks like a box sticking out from your main roof.
How It Works
Part of your existing roof is removed. A box-shaped structure is built projecting outwards from the roof slope, with vertical side walls and a back wall. This new structure is given its own flat or pitched roof. Large windows are fitted into the vertical walls, flooding the space with light.
The most common type in the UK is the flat roof dormer, typically built at the rear of properties. These provide maximum internal space because all the walls are vertical. Other types include pitched roof dormers (which look like small houses), shed dormers (single sloping roof), and L-shaped dormers (wrapping around corners).
Which Properties Suit Dormer Conversions
Dormers work on virtually any property with a pitched roof, including terraced, semi-detached, and detached houses. They’re particularly popular on Victorian and Edwardian properties in Solihull and properties throughout Warwick where they complement the existing architecture.
The versatility is their main advantage. Even properties with limited existing headroom can accommodate dormers because you’re creating new vertical walls rather than working within existing constraints.
Cost
Dormer conversions cost more than Velux because of the additional structural work required. A small 20 square metre dormer conversion costs £30,000 to £35,000. A mid-range 30 square metre dormer runs £40,000 to £45,000. A larger 64 square metre conversion with double bedroom and ensuite costs £45,000 to £50,000.
These figures are based on recent UK market data and include plastering, heating, plumbing, electrics, and carpentry, but typically exclude flooring and internal fixtures.
Value Added
Dormer conversions typically add 10% to 20% to property value depending on quality and what you create. Recent data from Nationwide Building Society shows that adding an extra bedroom through a loft conversion can add around 13% to property value, whilst adding a bedroom with ensuite can add up to 24% for three-bedroom properties.
Planning Permission
Many rear dormers fall under permitted development rights, meaning no planning permission is required. However, permitted development allows up to 40 cubic metres of additional roof space for terraced houses and 50 cubic metres for semi-detached or detached houses. The dormer can’t extend more than 0.3 metres above the existing roof ridge, and materials must match the existing house.
Front-facing dormers always require planning permission. Properties in conservation areas, national parks, or listed buildings face stricter controls and typically require permission.
What is a Hip to Gable Loft Conversion?
The Basics
A hip to gable conversion is specifically for properties with hipped roofs. A hipped roof is one where the side of the roof slopes inwards rather than ending in a vertical wall. This sloping side, called the “hip,” reduces the usable loft space considerably.
A hip to gable conversion removes that sloping hip and replaces it with a vertical gable wall, extending the roof ridge line outwards to meet this new wall. This transforms a hipped roof into a gable roof, creating significantly more usable space.
How It Works
The sloping hip section of the roof is removed. A vertical wall (the gable end) is built up to the height of the existing roof ridge. The roof ridge is extended to meet this new gable wall. The gap is filled with new roof structure and covering. Often, a large rear dormer is added at the same time to maximise space.
This is more complex structural work than a simple dormer because you’re fundamentally changing the roof’s geometry.
Which Properties Suit Hip to Gable Conversions
Hip to gable conversions only suit properties that have hipped roofs. These are most commonly found on semi-detached houses, end-of-terrace properties, and detached houses, particularly those built in the 1930s.
If you live in a mid-terrace property, you can’t do a hip to gable because terraced houses don’t have hipped ends. Some detached properties have hipped roofs on both sides, allowing for a double hip to gable conversion that creates enormous amounts of space.
This type of conversion is extremely popular on 1930s semis throughout Knowle, Dorridge, and Bentley Heath, where hipped roofs are standard and the conversion transforms cramped loft spaces into generous rooms.
Cost
Hip to gable conversions cost more than standard dormers due to the extensive structural work. Expect to pay £40,000 to £50,000 for a standard conversion on a 2 to 3 bedroom house, rising to £55,000 to £90,000 for larger or high-specification projects.
When combined with a rear dormer (which is common), costs increase further but you gain substantially more space.
Value Added
Hip to gable conversions can add 10% to 20% to property value. For properties where the hipped roof was severely limiting usable space, the improvement can be dramatic, potentially adding £50,000 to £75,000 to a typical Solihull semi-detached house worth £380,000.
Planning Permission
Hip to gable conversions often fall under permitted development for detached and semi-detached properties, with an allowance of 50 cubic metres of additional roof space. However, because the external appearance changes significantly, many require planning permission, particularly if you’re in a conservation area or if the gable will be visible from the street.
Comparing the Three Types Side by Side
Space Created
Velux conversions create the least additional space because you’re working within your existing roof structure. You gain a usable room, but floor area and headroom are limited by what already exists.
Dormer conversions create significantly more space by extending outwards and upwards. The vertical walls provide full-height standing room across a much larger floor area.
Hip to gable conversions, especially when combined with a dormer, create the most space. They’re transformative for properties with hipped roofs, often turning an awkward, cramped loft into a substantial room or even two bedrooms.
Visual Impact
Velux conversions have minimal visual impact. From the street, you typically see only the windows sitting flush in the roof. The property’s appearance remains largely unchanged.
Dormer conversions are more visible, particularly from the rear. Rear dormers are usually hidden from the street, which is why they often qualify for permitted development. Side or front dormers significantly change the property’s appearance.
Hip to gable conversions dramatically change the side elevation of your property. The transformation from sloping hip to vertical gable is obvious and permanent.
Complexity and Duration
Velux conversions are the simplest and quickest, typically taking 4 to 6 weeks to complete.
Dormer conversions are more complex, usually taking 6 to 12 weeks depending on size and specification.
Hip to gable conversions are the most complex, typically requiring 6 to 8 weeks minimum, often extending to 12 weeks when combined with dormers.
Which Adds Most Value?
This depends entirely on your starting point. For a property with excellent existing headroom, a Velux conversion delivers strong returns with minimal disruption. For most properties, a dormer conversion offers the best balance of cost, space created, and value added. For properties with hipped roofs, a hip to gable conversion is often essential to create genuinely usable space and delivers excellent returns.
Recent Nationwide research shows that well-executed loft conversions incorporating a bedroom and bathroom can add up to 24% to a three-bedroom property’s value.
Common Combinations That Work
Hip to Gable Plus Rear Dormer
This is the most common combination for semi-detached and detached properties with hipped roofs. The hip to gable creates the vertical side wall and extends usable floor area, whilst the rear dormer creates massive headroom and light. Together, they often create enough space for two bedrooms or a large master suite.
Velux Plus Small Dormer
Some properties use Velux windows on front-facing slopes (to avoid planning issues) and a small rear dormer to gain extra headroom where needed most. This keeps costs down whilst solving the headroom problem.
Making Your Choice: What Works in Solihull and Warwick?
For Victorian and Edwardian properties in Solihull and Warwick with generous existing loft spaces, Velux conversions often provide excellent value. They’re quick, relatively inexpensive, and don’t alter the property’s character.
For most terraced and semi-detached properties without hipped roofs, dormer conversions offer the best balance. They create substantial, usable space at reasonable cost and usually qualify for permitted development.
For 1930s semis throughout Knowle, Dorridge, Bentley Heath, and surrounding areas, hip to gable conversions (typically combined with rear dormers) are often the only way to create genuinely functional loft space. The investment is higher, but the transformation is dramatic.
The Use Your Space Approach
At Use Your Space, we assess your specific property to determine which type of conversion will deliver the best results. We don’t have a one-size-fits-all approach because different properties need different solutions.
Our surveys establish your existing headroom, roof structure, and limitations. We explain which conversion types your property can accommodate. We provide honest advice about which option offers the best value for your specific circumstances. We handle all design, structural calculations, planning (if required), building regulations, and construction.
Whether you need a straightforward Velux conversion in a Victorian villa in Warwick, a dormer conversion on a terraced house in Solihull, or a hip to gable transformation on a 1930s semi in Knowle, we bring the same commitment to quality execution.
Your Next Steps
Understanding the difference between Velux, dormer, and hip to gable conversions is the first step. The second is getting professional assessment of your specific property to determine which type suits your roof structure, budget, and needs.
Ready to explore how a loft conversion could enhance your Solihull or Warwick home? Contact Use Your Space today for an initial consultation. We’ll visit your property, discuss your aspirations, assess the possibilities, and provide honest advice about what’s achievable and what returns you might expect.
Our comprehensive approach means we handle every aspect from initial design through planning (if required), building regulations, and construction to final completion. Transform your unused loft space into the rooms your family needs whilst enhancing your property’s value.
Contact Use Your Space today to begin your loft conversion journey across Solihull, Warwick, Knowle, Dorridge, Bentley Heath, Shirley, Balsall Common, Leamington Spa, and Kenilworth.
