There are many ways to reduce your energy use while maintaining a pleasant working environment.
- How to create a well-lit environment
- Types of light
- Measure your light level
- Light for the size of the room
- Get expert advice on lighting
You need good levels and quality of light for staff to perform tasks accurately and efficiently. But that's not all – your people must interpret the lighting effect as a pleasant environment. There are a number of basic steps you can take to create a pleasant environment.
- Maximise natural daylight levels, but avoid glare.
- Choose light colours for walls and ceilings to help create a comfortable and pleasant environment.
- Use light sources with a high colour rendering index and a 4000 K colour temperature to improve visual comfort and to help keep staff alert.
- Allow zoning so people can dim lights or switch them off when they’re not needed, saving electricity and extending the time between maintenance checks.
- Wall or ceiling-mounted occupancy sensors should be set for a 10 minute delay (ultrasonic sensors are best as they pick up small movements such as typing at a desk).
- Place them so that there’s a line of sight between the sensor and any occupant.
- Make sure lights can be turned off manually. You may have enough daylight or task light in the office.
Lighter-coloured rooms distribute daylight better, creating spaces that feel more comfortable. So if you repaint a room, use lighter tones to brighten the space.
T5 fluorescent and LED are the best options for office lighting. There are two main types of fluorescent tubes - the older T8 and modern technology T5. T8 fluorescent fittings are still commonly specified by engineers and designers although LED and T5 fluorescents offer significant benefits in terms of running costs and lighting performance. Your lighting designer can discuss this in more detail.
Many offices are too bright, with light levels set for entire rooms rather than for separate areas. Areas where staff circulate generally need half the light of work areas. You can make significant energy savings by having lighting specifically set for your desk layout.
How to measure your lighting level
You'll need a good quality lux meter, which can be rented for around $100 per day. There are also a number of smartphone apps that can be freely or cheaply downloaded to get a rough indication of light levels. A high-quality lux meter should be used for stairwells or where machinery is used. Measure lux levels at 4 or 5 different points in each space, usually a couple of hours after sunrise or before sunset. If the space is mostly used at night, do the test at night.
Many New Zealand offices are overlit.
|Area||Ideal level of lighting|
Entrance foyers and reception areas
|Filing and storage rooms, walkways in open plan areas, seminar rooms||240 lux|
|Live storage fine material||160 lux|
|Passageways and toilet blocks Live storage bulky items||80 lux|
Lighting small offices
If you have a small office, vary the lighting level to suit the tasks at hand and for the amount of daylight that enters the space.
Typical reading and writing work in a small office requires lighting to 320 lux.
If you have a switching or control system, configure it so staff can adapt lighting levels. Install occupancy detectors to switch off lighting when rooms are empty.
If you have a dimmer switch, fit a secondary light switch so that you can switch off lamps when you don't need them.
Lighting large offices
Large spaces need to be lit for a range of tasks. You may have workspaces, conference and meeting spaces, material storage and circulation spaces.
- Limit glare from light fittings, windows and other bright surfaces.
- Design your lighting system as part of an integrated fit-out. Good lighting design should allow for desks to be located in an open-plan office without compromising lighting performance.
Lighting open-plan offices
Use ceiling-mounted occupancy sensors for each zone. To save energy, try a combination of daylight-reactive dimming control and occupancy detection.
Lighting conference, meeting and board rooms
Lighting should be adaptable for a range of tasks, such as detail work, informal discussion, slideshows and video conferences.
- Lighting on the meeting table should be at least 320 lux but you should be able to reduce this to around 240 lux for tasks that require less detail.
- You should be able to reduce light levels further for using data projectors and screens.
- Illuminate the walls to avoid contrast between people's faces and the background.
Lighting is a specialist area, so talk to a qualified lighting professional. They should be IES-accredited (illumination Engineers Society).
They’ll assess your specific needs and suggest the most appropriate energy efficient lighting designs and lamp options. Make sure you get a clear cost-benefit analysis of each lighting option. The analysis should include details about the return on your investment and ongoing maintenance costs.