Sheldon Peever Studio

What is the 45 Degree Angle Rule and Rights to Light?

The principle of rights to light is that a person has the right to natural light into their property by law. This is enforced by applying different mathematical rules. The most common of all being the 45 degree angle rule. A 45 degree line is taken from the centre of your neighbour’s window closest to the boundary with you (see opposite image). The area within the 45 degree spread can be developed, whilst the area outside of this area can not be developed and would automatically fail at planning stage. Additionally, there are other rules which apply for new build developments which are documented within the BRE Report Site layout planning for daylight and sunlight: a guide to good practice (BR209).

Do I need to carry out all the work I get permission for?

The simple answer is no, as long as the elements you do and do not want to build are separate.

An example would be if you get planning for a ground floor extension and loft conversion but decide to only proceed with the loft works or the other way round. You can do this without deviating from the planning approved drawings.

However, If you have planning permission for a double storey extension but only want to construct a single storey extension you would need to reapply for the amended design. Subject to discussion with the planning authority you may be able to apply for an amendment to the existing planning approval. Alternatively, you may need to reapply under a new application.

Can the building works be phased?

Your planning permission have a condition which states that building work has to be started within 3 years. There is no condition stating there being a time constraint on when works have to have been completed. Therefore, you can spread the work out over a longer time period by phasing if funds are limited.