The Right to Light Envelope – A limit and a target

At Rodic Davidson Architects, the majority of our projects are located within the densely built fabric of central London. Designing within this context comes with the constraints of adhering to specific planning policies and legislation pertaining to light.

A ‘Right to Light’ is a legal matter and is therefore distinct from planning considerations such as Sunlight, Daylight & Overshadowing assessments. A development may therefore be granted permission by planning authorities but halted by an injunction if the rights of a landowner or leaseholder were breached.

A right to light may be defined as a form of “easement that gives landowners the right to receive light through defined apertures in buildings on their land” (Law Commission: Rights to Light).

In defining the extent of the aperture, the amount of sunlight is irrelevant; it is instead measured in relation to the amount of sky visible from the working plane. A right to light is typically acquired when an opening has received light for more than 20 years. It may also be acquired if granted expressively or implicitly by deed.

Injury caused by encroaching on a protected light can be extremely costly to developers. In order to ensure a breach does not occur, we work with specialist consultants who create 3D right to light envelopes. These envelopes show the volume of space which may be developed without obstructing a protected light.

Where space is a premium commodity, the permitted right of light envelope becomes both a limit and a target. As such, this envelope becomes a significant factor in terms of the generation of form. We are working on some exciting new build schemes where this is the case and wonder if the right to light envelope is influencing a new mode of urban architecture…

Posted by Pippa with thanks to Aidan Cosgrave of Anstey Horne for his ‘Daylight, Sunlight and Rights of Light’ seminar at RDA offices on 10/10/2014.