This type of loft conversion is limited to the existing volume currently within the roof space. We would create a room/rooms within the existing shape of the roof at present using Velux windows for light and ventilation. We would not extend or alter the shape of the roof with this type of conversion.
Under standard planning regulations, planning permission is not required for this type of conversion. However, a full set of Architect's plans would be necessary along with the calculations of a Structural Engineer. This will be necessary to justify all current building regulations.
However, if your property is in a conservation area, there may be restrictions on the design and shape of the Velux windows to be installed. A planning advisor from AH Building Contractor will be more than happy to identify whether your property is in a conservation area or not.