Right to light and daylight assessment are different things

If your neighbour is building something that will block your light, you may have two quite separate positions and they run on different tracks. One is a right to light, which is a private legal right over your neighbour's land, enforced through the courts. The other is a planning objection about daylight and sunlight, which the council weighs when deciding the application.

You can win the planning argument and have no legal right at all. You can hold a strong legal right and still see permission granted. Confusing the two is the most common reason neighbours end up with neither.

The civil right and how it arises

A right to light is an easement. It attaches to a particular window or glazed opening, not to your garden, your patio or your house in general.

The usual way it arises is time. Where light has reached a defined window across neighbouring land for 20 years without interruption and without written consent, section 3 of the Prescription Act 1832 gives a right to continue receiving it. Rights can also be written into deeds, and they can be excluded by deeds, so the title documents for both properties matter.

Three things follow that surprise people.

A window you put in five years ago has no prescriptive right yet. A blank wall has none at all, however much light falls on it. And a lovely view of the sky from your garden is not a right to light, because there is no aperture involved.

This is general guidance rather than legal advice, and whether a right exists turns on title and on the history of the building, so take advice from a solicitor and a rights of light surveyor before relying on any of it.

The planning assessment and what it measures

When the council considers the application, loss of daylight and sunlight to your home is a material planning consideration. The usual yardstick is the Building Research Establishment guidance, BRE 209, which sets out tests for how much sky a window can see, how far daylight reaches into a room, and how many hours of sunlight a window receives across the year.

Those tests apply to habitable rooms. Main living rooms and kitchens carry most weight, bedrooms less, and bathrooms, utilities and hallways very little.

The guidance is advisory. A council can grant permission for a scheme that fails the BRE tests if it decides other considerations outweigh the harm, and it can refuse a scheme that passes them if the building is overbearing for other reasons. Where the applicant has submitted a Daylight and Sunlight Assessment, read it. The room-by-room results table is where the useful information sits, and it will tell you which of your windows the applicant has assessed and which they have not.

Why permission does not defeat a right to light

Planning permission is permission from the state to develop land. It does not hand your neighbour any of your rights, and it is no answer to a claim for infringement of an easement.

Courts have ordered parts of completed buildings to be taken down where a right to light was infringed, although damages are the more common outcome. The point for a neighbour is that the planning decision does not close the door. Your legal position survives it.

The reverse is also worth knowing. If you have no right to light, a council that grants permission has ended the matter so far as light is concerned, and there is no separate civil claim to fall back on.

One narrow exception exists. Where a local authority has acquired or appropriated land for planning purposes, statutory powers allow development that interferes with easements, with compensation payable instead. That applies to regeneration schemes involving the council, not to an ordinary private extension.

Remedies available in each system

The cost column is the one to read twice. Objecting costs nothing. A civil claim is expensive and carries the risk of paying the other side's costs if it fails, which is why most are settled rather than fought.

Evidence needed for each

They ask for different things, and material gathered for one is only partly useful for the other.

For the planning objection:

• The room and window affected, named by its use, with its position shown on a sketch plan.
• The distance from the window to the proposed wall, and the height of that wall above your window.
• Photographs taken from inside the room looking out, which officers find more persuasive than exterior shots.
• Any error you can identify in the applicant's own assessment, such as a room omitted or a use described wrongly.

For a right to light:

• The age of the window, from deeds, old photographs, historic maps or the property's planning history.
• The title documents for both properties, checked for any express grant or exclusion.
• A surveyor's analysis of how much light will remain in the room, because the legal test is about sufficiency rather than how much is lost.

That last distinction catches people out. In planning, a large reduction is the problem. In a legal claim, what matters is whether enough light is left, so a room that was very bright can lose a lot and still be adequately lit in law.

Sequencing a civil claim against an application

Order of events matters because building work, once done, is hard to undo.

1. Put the planning objection in during the consultation period. Keep it to planning matters: daylight, outlook, privacy, overbearing scale.
2. At the same time, take early advice on whether a right to light exists. Do not wait for the planning decision, because the 21 day consultation window and the legal position are on separate clocks.
3. If a right exists, tell your neighbour in writing before work starts, and say what you want changed. Many disputes settle at this point for the cost of a design amendment.
4. If permission is granted and your rights are being infringed, act before construction reaches the relevant level. Courts are far more willing to intervene before a building exists than after.
5. If the application is refused and your neighbour appeals, you can take part, and taking part in an appeal as an interested party explains how.

Getting in before submission is better still. A neighbour who raises a light concern while the drawings are being prepared sometimes gets the extension stepped in by half a metre, and nobody pays a surveyor, which is covered in getting involved before applications are submitted.

Getting advice from the right professional

Four different people, and asking the wrong one wastes a month.

A rights of light surveyor analyses whether a legal right exists and what remains after the development. A property solicitor deals with the title, the deeds and any claim or settlement. A planning consultant writes the planning objection and handles the appeal if there is one. And the council's case officer, who you can simply ring, will tell you what has been submitted and when the consultation closes.

If you think the council handled the application improperly, that is a different complaint again, and the council planning complaint process sets out the route.

Start with the case officer, because it is free, and the answer shapes everything else.