Hi,
Hope the information below is helpful.
Planning Permission
Planning permission is unnecessary if you don’t plan to alter the structure of the building so a garage conversion is permitted in most circumstances. If you live in a Listed building or a Conservation Area, planning permission may be required for even minor modifications. Homes in newly built estates sometimes require planning permission.
Standalone garages are more likely to require ‘change of use’ planning permission when converted to habitable rooms. Check with your local planning department by phone. If the answer is favorable, write the next day and ask for written confirmation.
Building Regulations
The change of use from a garage to a habitable room will mean compliance with building regulations, including delivery of a building notice to your council. Building regulations apply to ventilation, moisture proofing, insulation, fireproofing, escape routes, and structural soundness. As a result, almost any design decision must take them into account.
When dividing up the garage a new room is created. This room is subject to a set of building regulations that require an escape route and ventilation separate from the main room. Alterations such as an infill wall replacing the original garage door will also be subject to building regulations concerning the foundations. The building inspector will want to visually inspect windows, doors, fireproofing and foundations before he gives a certificate of completion.
You might want to hire an Architectural Designer which can do the Planning and Building Regulations Applications on your behalf.
Thank you.
ADM Studio