How Bright Should Your Space Be? A Guide to Lighting Levels
Every area of your project should be lit to the appropriate levels but you don’t have to just take a wild guess on how many light fittings you need.
Each space requires different light levels, and factors such as size, natural light, colour schemes, and personal preferences can all effect the final lighting scheme. This can make it complicated to calculate lighting levels, and levels are usually different for every project that we do. You can use this guide to get a rough estimate on the levels that you need, and if you need more help then our lighting design team can do all the hard work (and maths) for you!
We calculate the lighting level requirements based on the lux levels recommended by CIBSE (The Chartered Institute of Building Services Engineers). Lux is the measurement for how much an area is illuminated. The higher the lux level, the brighter and more well lit the space is. This is the metric measurement, however you might also see this area of illumination referred to as ‘foot-candles’ which is the imperial measurement (and a separate calculation).
Lux levels vary across different building types, but also different rooms and areas inside a building. They are also more of a guideline than a rule, and can be applied differently in different spaces (in a sultry bar vs. a fast food restaurant for example).
Lux level examples -
General Private Residence - 120 - 200 Lux
Education Classrooms - 300 Lux
Education Laboratories - 500 Lux
Retail Sales Area - 300 Lux
Retail Till Area - 500 Lux
Office Work Stations - 300 - 500 Lux
Office Lobbies & Entrance - 200 Lux
Using the recommended lux level for the space, along with the size of the area we’re lighting, we can calculate the amount of lumens required to light the space to the required lux level. This is a basic formula of -
Area of Space (m2) x Desired Brightness (Lux) = Required Lumens
Lumens are the measurement for the amount of light emitted by a bulb. Due to factors such as different bulb types and energy efficiency, wattage is no longer used to measure how bright a bulb is.
When we’ve calculated what our required lumens are, we can start choosing lighting to meet this level.
We could choose one single light that meets the lumen requirement, but due to factors such as the shape of the space, shadows, and the use of the space, this might not be the most efficient way to light your project. Our lighting designers use a variety of solutions to ‘layer’ different types of lighting. This layering staggers the light across different points using ambient, accent, and task lighting.
Ambient Lighting - The overall level of light, including all main lighting, task lighting, or added lighting.
Accent Lighting - Lighting which highlights specific areas such as pictures, ornaments, or areas of architectural interest. As a general rule, accent lighting is three times stronger than ambient light.
Task Lighting - Lighting for areas of specific work, such as reading, desk areas, kitchen counters, or other work areas.
There are so many different choices that can be made to reach the required lighting levels in a space, and these lighting calculations are just the first step! Our lighting design team doesn’t just do the maths for you. With over 35 years of lighting experience, we can recommend, source, and supply a variety of different lighting solutions across a range of different sectors.
