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Types of Loft Conversion Explained

Bedroom and bathroom in loft conversion
(Image credit: Simply Loft)

Understanding the types of loft conversion available will be crucial in making the right design choice for your own loft conversion project. 

A lot will depend on your property, whether it is detached, semi-detached or a terrace, as well as the style of the existing roof, as that will dictate the type of loft conversion you need and how much additional head height you require to create a usable space. 

Rooflight Loft Conversion

Rooflight loft conversion

(Image credit: Simply Loft)

This type of loft conversion is the cheapest and simplest to execute and is ideal for smaller spaces, perhaps where only one extra bedroom or an office is required. The existing lost space is kept as it is and rooflights are added.

In addition, the existing floor will need to be reinforced and, of course, stairs added. Electrics and plumbing, along with insulation, will be needed if the space is to be classed as useable.

Average cost: £35,000 - £40,000 (fully fitted out)

Dormer Loft Conversion

This type of loft conversion is as the above, but with the addition of dormer windows. This will increase the usable floorspace and can be used to add head height which gives you more options when it comes to placement of the stairs.

Dormer loft conversions are good where the pitch angle is high, as the useful floor area can be increased.

Average cost: from £40,000 - £45,000 

Installing a dormer window in a loft conversion

(Image credit: getty images)

Hip-to-Gable Loft Conversion

In a hip-to-gable loft conversion, the hipped, slanted section of the roof is converted to become a vertical wall (gable end). This is then given a standard pitched roof that creates a space internally with full headroom. The vertical wall also allows for standard window openings.

For maximum space, consider combining a hip to gable loft conversion with a dormer conversion.

Average cost: from £35,000 but up to £70,000

Hip to gable loft conversion by Econoloft

Hip-to-gable loft conversion by Econoloft (Image credit: Econoloft)

Mansard Loft Conversion

Mansard loft conversion

(Image credit: Simply Loft)

A mansard loft conversion can pretty much add a whole additional storey to your home. It involves changing a sloping roof structure resulting in a wall that is almost vertical — typically 72 degrees. The final roof is flat. The majority of mansard loft conversions run from one gable wall to another.

It is also possible to have a double mansard roof — at the front and rear of the house.

Average cost: from £45,000 but easily upwards of £80,000  

Michael is HB&R’s Head of Content and Product Development. Michael is also, Chair of the National Custom and Self Build Association (NaCSBA), presenter of multiple property TV shows and author of Renovating for Profit (Ebury). Michael is a regular in the seminar theatres and Advice Centre at the Homebuilding & Renovating Show.