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Does the proposed lighting solution comply with current building regulations?

In the UK, any new construction or major refurbishment project must comply with the 2013 Building Regulations. Regulation requirements include:

  • A minimum efficiency for lighting fixtures at 60 lumens per circuit-Watt in the system. Lower efficiency luminaires are permitted only when fitted with particular types of lighting controls
  • sufficient illuminance levels for each work task Illuminance (or light) levels indicate the amount of light required for performing a task in a safe and efficient manner. In the UK, illuminance levels are published primarily by the Society for Lighting and Light (SLL). Most publications, guidance and legislation refer to these or are in line with them. Please see examples of activities and their associated maintained illuminance levels in the card titled Check whether your lighting design meets the standards of the Health and Safety Executive's 'HSG 38: Lighting at Work.'
  • appropriate ‘unified glare rating’ (UGL) factor The luminance from the lamps divided by the background luminance from the room's walls and ceiling. This varies depending on elements such as the dimensions of the space and the technical properties of its lamps and luminaires. According to the ‘SSL Lighting Guide 07: Offices’ the unified glare factor for office spaces should not exceed 19.
  • appropriate contrast levels between different areas of a building
  • appropriate brightness levels of various surfaces such as walls and ceilings

Another method for complying with the 2013 Building Regulations’ energy efficiency requirements for lighting systems is the Lighting Energy Numeric Indicator, LENI.

The LENI method calculates the energy performance of a lighting system in terms of energy consumed per square metre of floor area per year (kWh/m2/yr). Use of LENI promotes efficient use of lighting, not just efficiency of individual lighting components, as was the case for the previous edition of the Building Regulations. In doing so, it recognises the importance of lighting control.

Further reading:

  • HM Government’s Non-Domestic Building Services Compliance Guide 2013:
  • The LIA Mini Guide to Part L for the Building Regulations (available to registered members only):