This light loss is primarily due to the distance between the fixture and the target surface. To achieve a desired illuminance level (foot-candles) at a target point (like a desk surface), we need to account for light loss between the light source and the target. Candela indicates the luminous intensity at the center of the light source in a specific direction. If your ceiling height is below 10ft, our lumens calculator will be sufficient for determining the required light output for your application.įor ceiling heights exceeding 10 feet, we’ll need to understand candela ( cd), or center beam candlepower. Note: Only read this section if your ceiling height is taller than 10ft. A 100-square foot dining room, which needs 40 foot-candles, will need 4,000 lumens.ĭownload Free IES Footcandle Recommendations by Application Index » Ceiling Height Variable For example, a 100-square foot living room, which needs 20 foot candles, will need 2,000 lumens. Multiply your room square footage by the footcandle requirement. Let’s recap how to gauge how much light you need for a space. Summary: Calculating Total Lumens Needed for a Room Residential Lighting Footcandle Requirements Room Footcandle Requirements for Various Applications Commercial Lighting Footcandle Requirements Room We’ve created a helpful guide to How Many Lumens You Need that walks you through this calculation in more detail. A 100 square-foot dining room, which needs 40 foot-candles, will require 4,000 lumens. For example, a 100 square-foot living room, which needs 20 foot-candles, will need 2,000 lumens. Multiply the room square footage by the footcandle requirement.Once you establish the intended use of your space, browse this footcandle chart for the IES-recommended footcandle requirement for your application. For example, a bathroom or kitchen will require more footcandles than a living room or bedroom. Lighting requirements vary depending on the type of room being lit, also known as the application. Establish the footcandle requirement for your application.For example, if the room is 10 feet wide and 10 feet long, the room square footage will be 100 square feet. Multiply the length times the width of the room to get the room square footage. Determine room size by square footage.The Lumen Method – How to Calculate Total Lumens Needed Please note that these ratios may vary slightly, even between different LED products. If a 100-watt incandescent light produces 1,500 lumens, and a 10-watt LED light does the same, the 10-watt LED bulb may claim 100-watt equivalency and energy efficiency. Wattage is a measure of how much electricity (or energy) a light bulb consumes to achieve its lumen output.Įach type of light source - LED, fluorescent, halogen or incandescent bulbs - has a different lumen-to-watt ratio.

LED lights provide higher Color Rendering Index (CRI), so, while they more accurately reveal the colors of the subject being lighted, they don’t provide more light. Strictly speaking, 600 LED lumens provides the same amount of light as 600 incandescent lumens. The reference point: A standard 100-watt incandescent light bulb produces about 1,500-1,700 lumens. It’s also commonly known as brightness or light output. Lumen output is a measurement of the total quantity of visible light emitted by a light source. For exact analysis, please consult a lighting design professional.

1200 lumen light