Do You Need Planning Permission for Skylights and Roof Windows?

Permitted development rules outline what alterations you can make to your property without seeking planning permission.

You can install or replace roof windows under permitted development subject to the following conditions:

• The window will not protrude more than 15cm above the roof's plane.
• The window will not protrude over the roof ridge or be higher than the roof's highest point.
• Any side-facing windows that are more than 1.7m above the ground and overlooking neighbours must be obscure-glazed.
• Any side-facing windows under 1.7m above the ground must not be able to be opened.
• No changes are made to the chimney, flue, soil or vent pipe, or solar panels.

How to Choose a Roof Window Installer

Is My Roof Suitable for a Roof Window?

Whether you need planning permission to install your new roof windows or not, you must still follow any relevant building regulations outlined in the Planning Portal, and seek building regulations approval for any work you have carried out.

By law, all modifications to buildings must comply with these regulations, which highlight the minimum legal standards for design and safety. Of particular importance with regards to roof windows are section J and section L of the building regulations, which deal with energy efficiency, thermal insulation, and protection against fire.

Adding new or altering existing roof windows can undermine the integrity of the building, so special care must be taken to ensure that the roof continues to perform as it should and meet all building regulations requirements. This is because:

• The roof structure will likely need to be altered to create the opening.

• The roof will have to carry the weight of the new skylight and may need to be strengthened.
• The roof window must be sufficiently insulated for energy efficiency.
• Unplanned movement can occur as a result of any structural works.

Please note: If the work is being carried out by a professional tradesperson who is registered with a competent person scheme, they can self-certify that any works meet the building regulation standards themselves. If you would like your roof windows to be installed without any hassle, we recommend hiring a professional team with years of experience to carry out the work for you.