Building above an attached garage is treated the same as adding a storey to the rest of your home. This is considered to be permitted development, not requiring an application for planning permission provided you meet the set rules and requirements.
You will still need to submit an application for prior approval to your local planning authority.
Read the list of rules and requirements for extending upwards.
Many homeowners choose to replace their traditional polycarbonate conservatory roof with a solid tiled roof for better thermal efficiency.
If the change significantly alters the structure or appearance of the roof, then planning permission may be required. Most alterations to roofs are considered permitted development, providing they meet the limits set out in legislation.
A new roof must comply with building regulations to ensure it is structurally safe, energy efficient and properly ventilated.
If you want formal confirmation that the existing use of a building is lawful for planning purposes, or that your proposed development does not require planning permission, you can apply for a Lawful Development Certificate(LDC). An LDC can be useful in situations where you need assurance that a particular use, operation, or development is lawful under planning legislation.
Read more about Lawful Development Certificates.
Applications for a Lawful Development Certificate can be submitted online to your local council using Planning Portal. You must include enough detail and evidence to support your case; if the information is insufficient, your application may be refused.
If the garage will remain in domestic use - for example, as a personal hobby or home workshop - then planning permission is typically not required.
However, it’s important to check whether there are any planning conditions, covenants, or restrictions attached to your property or the garage itself that may limit or prevent conversion.
Read about planning permission for garage conversions on Planning Portal.
The UK Government provide access to public land records, allowing you to check certain restrictions on land. You can use the online tool to check whether your land is in a conservation area.
VisitGOV.UK and use the planning data map.
(This map covers planning data for England).
If you are unsure you should contact your local planning authority.
Planning permission may be required for external insulation if it impacts the external appearance of the building. If materials are of a similar appearance to those used in the construction of the house, then permission will likely not be required.
Listed buildings will require listed building consent for any significant work.
If you live in a Conservation Area or other protected area you will need to apply for planning permission before making changes to the outside of your house.
Further information and building regulations advice is available on Planning Portal. Read our external walls common project.