National Association of Rooflight Manufacturers Study

Designing with natural daylight and controlled artificial light to reduce CO2 emissions – new document available

A document jointly prepared by NARM, the National Association of Rooflight Manufacturers and LIF, the Lighting Industry Federation, sheds light on using rooflights and vertical glazing in combination with automatic lighting controls to significantly reduce energy consumption, with associated reductions in greenhouse gas emissions.


Artificial lighting is essential during parts of the working day, particularly in winter, but at other times may not be needed at all. In order to minimise the use of electricity, and maximise the benefits of daylight, artificial lighting should be effectively managed by automatic controls. Natural illumination through rooflights is completely free and provides some useful solar gain along with a quality of light that makes the work place a pleasant environment, with beneficial effects for people inside the building.


Recent research demonstrates that increasing rooflight areas has a beneficial effect on carbon emissions by reducing the demand on artificial lighting. This is contrary to the previously widespread view that large rooflight areas created greater heat loss and consequently higher energy usage. Advances in the thermal efficiency of rooflights have changed the balance in favour of larger rooflight areas.


The new NARM/LIF document provides detailed information relating to compliance with Part L2A and 2B and the considerable savings that can be achieved by bringing daylight into a building through rooflights and windows and coupling this natural light with automatic controls that dim, or switch off, the lights during the day.


There are comprehensive sections covering designing with rooflights; automatic lighting controls and the future of Part L, as well as comparisons between different lighting systems and luminaries. However, please bear in mind, here at Panoroof our London Roof Lights are manufactured with NARM/LIF regulations in mind.