In the build of offices and workplaces there are regulations and standards that should be met. Included in these criteria are the set of rules and considerations relating to the provision of lighting.
When speaking of lighting standards (suggested targets rather than enforceable law), there are a number that should be adhered to. Our team at GDS will use our extensive knowledge to ensure your project meets these.
Regulations vary from region to region, but we’ll make certain you meet those applicable to the location of your build.
The Society of Light and Lighting are a part of The Chartered Institution of Building Services Engineers, and writers of SLL lighting guides. Their aim is to utilise good lighting and design as a means of creating a healthy, ergonomic and sustainable future in engineering and building.
Find out more at https://www.cibse.org/society-of-light-and-lighting-sll/about-sll
LG3 is a now defunct lighting guide, intended for the improvement of display and screen use. LG3 was released and implemented in 1989, updated with the Health and Safety DSE regulations in 1996. In the addendum of 2001, it considered changing standards internationally and the latest technology. LG3’s primary consideration was how lighting is required to differ in situations where there are computers and screens, providing suggestions for lighting schemes. Further minor amendments were added at later dates to LG3, these were largely on the issue of natural light causing glare through doors and windows.
CIBSE’s current office lighting guide, ‘LG7’ builds on the defunct LG3. Focus is on minimum lumen levels across a range of spaces in an office or workplace. Adhering of LG7 guidelines should ensure that lighting in the office or workplace is comfortable, safe for working conditions and provides essential stimulation to occupants. Published in 2005, the guide received a significant update in 2012. The 2012 update brought it into line with BS EN 12464 (detailed later).
LG7 puts focus on design options for luminaires, with guidelines for utilising direct and indirect, task and localised areas of lighting. Also covered is the role of natural lighting in design and consequently there are sections devoted to effect for glare on employees.
LG7 and LG10 give guidance to avoidance of forms of glare; Disability (when glare impairs the view of an object) and Discomfort (Glare that causes a person discomfort).
An installation’s potential for discomfort glare, from artificial lighting is calculated using UGR. This calculation is made by the luminance of light sources, their apparent size, location within the field of view and luminance of the general environment.
Difficulties with Glare? Discuss your requirements with our lighting design team on +44 (0) 117 325 0063
LG7 makes it clear that it is of paramount importance to provide a sufficient level of illuminance to objects and other people interacted with in a space. Therefore, LUX levels for the different areas of the workplace have been clarified in the guide.
It is recommended that task areas should be illuminated to between 300 to 500 lux (although this can vary dependent on the task, see the table below). In all workspaces it is prudent to make use of lighting control systems but meeting rooms, which often host presentations require this as a default.
In order to avoid eye strain, it is best practice to provide occupants an area of space in which to look (ideally to an external space providing natural light), allowing them to break from their view of their localised area. If this additional space cannot be achieved it is of paramount importance to provide a similar level of illumination on walls and ceilings to the task area (see image below).
The guide states the illuminance needed for areas less considered such as walls (75 lux) and ceilings (50 lux). In addition, covered in this guide is the best practices for integrating control systems and daylight into a scheme, whilst limiting reflection and glare.
Uncertain what illuminance you need for a certain area? Discuss your requirements with our lighting design team on +44 (0) 117 325 0063
In addition to the required LUX levels and UGR ratings, Colour Temperature (CCT) is important in making a task areas and break-out spaces as comfortable for users. The use of Warm CCTs (i.e. 2700K) are perfect for creating relaxed environment, great in ensuring staff can get proper downtime. Cool white light (i.e. 4000K) creates an environment perfect for focus and high CCTs of 6000K and above can cause colours of a space to be misrepresented.
Our Reality lighting products all fall within 2700K-4000K.
Other lighting guides of importance and consideration include LG10, LG11 and LG16.
LG10 is a guide to design, taking into account the use of day and other natural light. It addresses issues pertaining to architecture including aesthetical appearance and building physics.
Talk to our team today or refer to the link for additional information on the use of natural lighting in design – https://www.cibse.org/networks/groups/daylight/daylight-past-presentations
LG11 looks at the role of surface reflectance in specification and its measurement in design.
The LG16 guide looks at the where to measure and calculate light on stairs so that the positioning of luminaires does not present an impact risk for those using the stairs in any capacity.
Our lighting designers are experts in the use of natural lighting in design, the effect of surface reflectance and stairway lighting, for expert advice talk to design team on 0117 325 0063 or connect with our head of lighting design, Irena on LinkedIn (https://www.linkedin.com/in/irena-kovacevic-0197749b/).
Split into three main areas to provide a comprehensive guide to; ‘Daylight and Energy Use’, ‘Visual comfort and performance’ and the ‘artificial lighting in CAT A, B and Shell and Core Fit-Outs’.
Each section references the other guides and national and international regulations to provide perhaps the most comprehensive guide to these subject areas.
The GDS crew have these handbooks on their desks so if you need any advice on any area of the book talk to us today.
BS EN 12464 sets out guidelines relating to the standard of lighting in offices/indoor workplaces. Amongst the primary concerns of the guide is how lighting effects visual tasks and the use of display screen equipment. It also encourages the use of lighting control systems designed carefully to positively react to the building’s layout, use and external climate factors. The consideration of external factors means that there is a deep analysis of natural lighting and how the artificial light sources should be used in its absence (resulting in energy savings). As with LG7, the minimum wall and ceiling illuminance is detailed.
According to BS EN 12464-1 the average task illumination for a writing or typing (task) area in an office should be around 500 lux. For task areas where computers are used predominantly, it is recommended in the LG7 guide (referred to earlier) that there should be around 300 lux.
The WELL Building Standard was designed as a reaction to increasing economic development that has resulted in increased human impact on the world. The WELL Building Standard is a performance-based system (developed by Cundall) for monitoring features of the built environment that impact human health and well-being. One of the areas looked at in this standard is the impact of lighting on health and well-being. WELL gives pre-conditions to achieve in order for a business to obtain certification and also offers further optimisations that can be adhered to in order to gain a higher level of certification.
Revised on numerous occasions during the 90s and finalised in 2004, Part L is a building regulation pertaining to energy consumption levels. Within Part L there are number of sub-sections specific to lighting; Part L1A, which relates to lighting for new dwelling builds and Part L1B, which relates to existing dwellings. In addition, Part L2A refers to new builds that are not dwellings and L2B deals with existing non-dwelling builds (in instances where the floor area is 100m2 or over). In Part L1A and B it is stipulated that 75% of all fittings should be low energy consumption (at least 400 lumens per circuit Watt) and that said low energy luminaires must be used every 25m2. In Part L1 it is stipulated that external light fittings must not exceed 150W and that they must have controls to save energy at times of plentiful natural light. External luminaires must also achieve an efficacy of 40lm/W. Part L2 A&B both dictate that efficacy be at least 50 lm/W for general lighting and 22 lm/W for display lighting. The primary focus of Part L is to ensure that natural light is utilised to as great an extend as is feasibly possible and consequently artificial light is merely to be used as subsidy.
Part L2A&B brought in LENI as an alternate means of showing compliance. LENI looks at the efficiency of all fittings within an installation, with a focus on the use of responsive controls. LENI is expressed as energy consumption per square metre per year (kWh/m2/yr). kWh/m2/yr must not exceed a pre-agreed figure and additionally fixtures must not be switched on in excess of the calculated required light to subsidise natural light levels.
Find out more about LENI here. More information coming soon.
Both LEED (Leadership in Energy and Environmental Design) and BREEAM (Building Research Establishment Environmental Assessment Methodology) are certification programs that can be achieved by obtaining their defined levels of environmental consciousness in building design.
The LEED certification (run by the non-profit US Green Building Council) is the significantly more prominent worldwide, with over 50,000 builds receiving the certification, however very few of these are in the UK, where BREEAM largely dominates.
BREEAM is very much an institution within UK building certification, due largely to its principles being embedding within national regulations. However, BREEAM unlike LEAD is no longer run by a non-profit organisation.
In the case of BREEAM, the assessment is carried out by assessors that examine evidence against the pre-defined credit checklist before sending it to the Building Research Establishment (BRE) for approval. In contrast, for the LEED scheme, it is the designers who collect and send the evidence to the US Green Building Council to assess. Consequently, this means for BREEAM schemes, that much of the effort of submission is carried about by the assessor (however this scheme is generally considered to be more prescriptive).
The focus of the two schemes alters too, with LEED prioritising individual product certifications, and BREEAM assessing the company, investigating the likes of product supply chains and responsible production.
Should you wish to discuss which certification makes more sense for your build then please give us a call on 0117 325 0063 or you can read more at https://www.breeam.com/discover/how-breeam-certification-works/ and https://new.usgbc.org/leed.