How to calculate the intensity of light needed in your environment?

What's the limit of lighting? This question can be hard to answer, but when you need to calculate how much LED lighting is needed to create a well-lit space, it becomes even more dense.

Whether it’s LED lighting for commercial spaces or homes, find out in this article how to determine how many lumens you need to properly light your space.

First, focus on the technical terms:

Lumens – A measure of light emitted by a source, whether it’s LED, fluorescent, halogen or incandescent. Also known as “glow” or “light output”. For your reference: a standard 100 watt incandescent lamp produces 1,500 to 1,700 lumens.

Watts – Measure of the amount of electricity (or energy) consumed by a light to achieve the claimed brightness. Each type of light source, LED, fluorescent, halogen or incandescent, has a different lumen-watt ratio.

Power Equivalence – If a 100 watt incandescent produces 1,500 lumens and a 10 watt LED does the same, the 10 watt LED can advertise the equivalent of 100 watts on its label.

Efficiency – The number of lumens that a light produces for each watt it consumes. The higher the number, the more efficient the light is.

Now, how much light is enough?

Set the area of your environment. Multiply the length times the width of the space to obtain the square meters. For example, if the room is 10 feet wide and 10 feet length (approximately 3 meters), the area will be 100 square feet (or approximately 9m²). For the generic space of 250 square feet (approx. 23 m²), you will need about 5,000 lumens as the main light source (20 lumens x 250 square meters). In your dining room, for example, you should choose about 30 lumens per square foot on the table (you want to see the food, not examine it), so if your table is 6 x 3 feet (approx. 2m x 1m) , that means 540 lumens.

Set the intensity of the lighting according to the utility you’ll give it. Intensity is how bright the light is at a distance of 1 foot (approximately 30 cm) from its source.

The lighting requirements, of course, depended on the type of environment to be lit. For example, a bathroom or kitchen require much more intensity than a room.

Take into account some aspects: if you have very dark walls and furniture or if you are using shaded lamps, you will need approximately 10 lumens per square foot.

Personal preference, of course, is one that will dictate the final decision. Generally, the best approach for most spaces is to over-size and install light dimmers to reduce the light level.