- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 02 Mar 2018
Windows are openings fitted with glass to admit light and allow people to see out. They are often openable to allow ventilation. Rooflights (sometimes described as ‘roof lights’ or ‘skylights’) are windows built into the roof of a building.
|A dome light, lantern light, skylight, ridge light, glazed barrel vault or other element intended to admit daylight through a roof.|
Rooflights are effective at allowing natural light deep into the centre of a building, particularly where it is not possible to install windows in perimeter walls or where privacy is needed. Where they are openable, they can also be effective at promoting natural ventilation, as they tend to be at the top of buildings and so can benefit from the stack effect. They may also be used to allow access to roofs or to roof terraces.
Some rooflights however can be seen as a poor design solution, contributing little to the architectural form of a building, and simply creating a hole in a roof because without them there would be insufficient natural light. They can also suffer from ponding, dirt accumulation and staining.
Rooflights must have safety glazing, and if they are out of reach, may need a mechanism or motor to open them.
BS EN 14351-1 (Windows and doors. Product standard, performance characteristics. Windows and external pedestrian doorsets) suggests that the term ‘roof window’ refers to a window that is in the same plane as the surrounding roof, and has a minimum pitch of 15 degrees. This is as opposed to 'rooflights' which by this definition are installed on an upstand, and so are not in the same plane as the surrounding roof.
 Related articles on Designing Buildings Wiki
Featured articles and news
The Isle of Man’s naturally-occurring materials and distinctive building techniques.
BRE partner with Global GreenTag to develop an Ethical Labour Sourcing Standard for Australia.
The Chartered Quality Institute explain the pathway to success for organisations implementing management systems.
An introductory article looking at where a duty of care can arise in the construction industry.
House of Lords committee encourages the use of off-site manufacturing in new report.
Computational fluid dynamics (CFD) can go some way to show the impact of new buildings on their surroundings.
The shortlist for the 2018 prize for the UK's best new building is revealed.
Amendment to Bill aims to provide councils with greater powers to increase tax premiums on empty homes.
As the latest summer blockbuster 'Skyscraper' is released, we look at some of the best uses of buildings in film.
Read our introductory article on how to layout a building.