Last edited 04 Sep 2020

Rights to light

1 Introduction
2 Interpretation
3 Obstruction
4 Measurement
5 Rules of thumb
6 Remedies
7 Recent considerations
8 Related articles on Designing Buildings Wiki
9 External references

[edit] Introduction

The right to light in the UK goes back to general property law relating to easements that from the rule of William IV. The Ancient Lights Law was superseded by the 1832 Prescription Act.

Rights to light generally become an issue when a new development, or proposed development affects the access to light of an adjoining property. Rights to light also apply to obstructions caused by trees, hedges and so on, but there are no rights to light for open ground.

Rights to light can be the result of 'easements', or can be ‘nuisance’ issues.

An easement is a a right which a person has over land owned by someone else. An easement can be created by express grant (for example it may be set out in a conveyance deed), by necessity (for example if there is only one means of access to a site) or by prescription (the act has been repeated for at least 20 years). Easements are normally attached to the land. In relation to rights to light, an easement can perpetuate even if a new building is constructed. This means that it cannot be assumed that no rights to light exist simply because neighbouring buildings appear to be new.
Private nuisance regulates interference with a persons right to enjoy land, or some right in connection with that land. Such interference must be ‘unreasonable’ to constitute nuisance. Nuisance can be remedied by an injunction, abatement and/or damages.

[edit] Interpretation

Generally, a right to light refers to the right to receive sufficient light through an opening (such as a window), allowing ‘ordinary’ comfortable use and enjoyment of a dwelling, or ‘ordinary’ beneficial use and occupation of other buildings.

The levels of acceptable light have not been objectively quantified and are instead assessed on a case-by-case basis by the courts. The terms 'sufficient light according to the ordinary notions of mankind' and 'tangible deprivation to a building' have earned substantial fees for the legal and surveying professions and given rise to specialists and expert witnesses in this field.

Much depends on:

The measurement of light.
Proof of its diminution.
The damage caused by obstruction.

[edit] Obstruction

Windows can be of different sizes, heights and quantity and serve varying room sizes with natural light. Generally, the larger the area served by a window, the more value can be put on to the window.

The obstruction of light between an internal space of the dominant property and the sky by a servient property is generally caused either by the height, width or proximity of the offending structure. The general law on easement does not allow a servient property to benefit in value at the expense of the dominant property if the latter has enjoyed uninterrupted rights for twenty years or more.

[edit] Measurement

It is now relatively straightforward to measure, or model lighting levels on working planes within buildings and to assess whether there is currently adequate light to perform tasks such as reading, or whether there will be once a proposed development is constructed.

[edit] Rules of thumb

The '45 degree rule', which may be used to assess planning applications for developments impacting on windows, is not used to assess rights to light.

The '50:50 rule' however, may be deemed adequate. This involves determining what percentage of a room receives adequate light on a working plane 850 mm above the floor. An injury may be considered to have occurred where the percentage is reduced to less than 50%. Where more than 50% of the room still receives adequate light however, an injury may not be considered to have occurred, irrespective of the amount of light that has been lost.

[edit] Remedies

The most likely remedy to a loss of a right to light is an injunction. Courts do not like to award damages in such cases, as this could be seen as a developer being able to ‘buy’ the rights of another. However, if damages are awarded, they may be based on:

The historical use and purpose of the rooms affected by the infringement.
The loss of natural light power over the affected by the obstruction.
The additional value to the property of the servient offender. This may be a proportion of the developers profits, where the proportion relates to the amount of floor space that the developer could not have built if they had not infringed on the right to light of their neighbour.
Any loss of residual value to the dominant property

The law and possible remedies surrounding rights to light are not straightforward. There are complications in relation to some Crown land, statutory bodies and compulsory purchase, and under certain circumstances developers can obtain light obstruction notices. For more information, see Light obstruction notices.

If it is possible that a development will encounter rights to light issues, a right to light consultant can be appointed to give expert advice.

In practice, the dominant property can hold up a development for a very long time by means of an interlocutory injunction. The delay caused while the case goes through the courts, particularly if it is appealed, can bring everything to a halt. So a negotiation generally takes place, with the dominant owner’s team having a good idea of the value of the infringement to the servient owner, and a deal is done or the design is changed to step back any light obstructing structures.

[edit] Recent considerations

Until recently, it was considered that a right to light by prescription may be lost if a person submits to a loss of light for a year before making a claim. This means that complaints should be made quickly, and repeated frequently to ensure that the right is not lost before the claim is made. However, the case of HKRUK II (CHC) Ltd v Heaney (2010) suggests that time may no longer be a barrier to an injunction.