Understanding Loft Conversion Categories

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Ben Wilson | 23/06/16

Loft conversions are a fantastic way to increase the living space within your property without having to compromise on garden space and in some instances converting your loft space can be undertaken within permitted development https://goo.gl/Aq75Fx .  

With advances in the number of ways a loft space can be converted,  there is now an option for all homes (subject to planning permission where required).  The type of loft conversion is determined by the property style, roof height, available space, conservation area, local planning regulations, your budget, and needs.


There are 4 main and widely undertaken categories of loft conversion:

Rooflight Conversion
The existing roof space is converted with no increase in the volume other than the simple addition of roof lights to the front and back and the roofline is unaltered leaving the original roof structure untouched. Windows may also be added to the gable walls. This is the most cost-effective option as it involves minimal alteration to the structure and planning is seldom required.  

Dormer Conversion
A dormer loft conversion is a structural extension which projects vertically from the plane of a sloping roof. Dormer windows are added creating additional floor space and headroom within the property.  Due to the added internal space and the fact that in most cases this type of conversion falls within the category of permitted development this type of conversion is popular. 

Hip-to-Gable Conversion
When a roof slopes down to the eaves on all sides it is known as a ‘hipped’ roof.  With this type of conversion one or more hips (depending on whether your property is semi or detached) can be replaced by a gable wall and the roof extended over the gables.  Internal space is often limited with this type of roof structure, therefore for a conversion to be practical a hip-to-gable conversion is the obvious choice. As this type of loft conversion changes the outline of the roof, planning permissions may well be required but quite often can still fall within permitted development. You could also combine the last two options and do a hip to gable and rear dormer conversion, which maximises the potential of new living space. Depending on the increased volume of the property this option can also fall within permitted development. 

Mansard Conversion
This type of conversion has a flat roof, with the back wall sloping inwards at an angle of 72 degrees, it replaces the original roof with a new box-like structure that effectively adds another full storey.  Windows are usually housed within small dormers.  Add an additional mansard to the front as well and this becomes known as a double mansard. Due to the enormity of the changes to the roof shape and structure planning permission is generally required. 

For more information on undertaking a loft conversion with Upright visit http://uprightconstruction.co.uk/services/loft-conversions

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