Imagine nursing a building project from first idea to glorious reality, only to find that the court orders you to demolish it. Suitably chilled? Now read on

It is an ancient right, but when developers start describing it as one of the most important obstacles they face, you can be sure that age has not withered the strength of this law.

In urban areas where space is at a premium, if rights of light exist, they must not be ignored. One of the most important recent Appeal Court rulings, Regan vs Paul Properties, ordered the demolition of a building infringing light. It was the first such ruling in 20 years, and it shook developers, who thought the judicial trend was away from such injunctions.

Establishing the existence of rights usually involves a detailed review of title documents and the appointment of a rights to light consultant. Generally, a right of light is the right to receive natural light through defined apertures (such as windows, skylights or glazed doors).

Such rights can be acquired by any property. There are no distinctions between residential and commercial properties provided they have a relevant aperture. Further, the acquisition of a right of light is not limited to the freeholder of a property. Tenants can also acquire rights.

Generally, the person with the benefit of a right of light is entitled to a level of light that is sufficient for the comfortable enjoyment of the property. If the level of light falls below this, there may be an actionable interference.

When assessing the extent of the interference, it’s not the level of light lost that is assessed but the amount that remains. If that is too low, the affected person may seek an injunction to prevent the development, require it to be cut back, or get it demolished.

Alternatively the owner could be awarded damages to compensate for the loss of light. These may be significant – sometimes three times the actual reduction in value of the affected property or a percentage (usually 5-15%) of the developer’s profit.

Here are some tips for owners and occupiers:

• Don’t ignore light obstruction notices. Failing to take these seriously could result in the loss of any rights to light

In Regan vs Paul the court ordered the demolition of a building. It was the first such ruling in 20 years, and it shook developers

• Identify your rights of light – as soon as you, the owner or occupier, become aware of a potential infringement to your light, you should act immediately. Check the deeds to establish whether there are any formal rights granted and assess whether you do have a right

• Appoint a right of light consultant to assess any infringement by the proposed development and any damage that could be suffered as a result

• Identify your strategy. Is it to prevent the development or obtain financial compensation? Keep all options open and reserve your position to seek an injunction to prevent interference with any rights. Ensure any discussion about cash settlements is without prejudice and reject any open offers. If any offers for cash settlements are received these should be rejected, although without prejudice discussion could take place.

And some tips for developers:

• Be aware of your neighbours’ rights from the outset and obtain specialist rights of light advice (both legal and surveyor) early

• Consider a strategy early on for eliminating or reducing the risk of a claim. A different strategy may be required for residential as opposed to commercial occupiers. It’s not unreasonable to assume that financial payment may be adequate compensation for a commercial occupier but not for a residential occupier

• If rights of light cannot be dealt with by negotiation, the risk of an injunction remains. In deciding on injunctions the courts assess the behaviour of the parties and whether the loss of a right can be adequately dealt with with money. Offers of compensation should be made on an open basis to try to create evidence that compensation would be adequate

• At the outset of a project it may be worth registering a light obstruction notice against neighbouring properties. Affected parties have one year to object to the registration. If they do not, this can defeat later claims.