How To: Calculate Lumens Required for Any Room

May 28th 2014

In a previous post, we showed you the method of how to calculate wattage needed for any room. You can also use this method to calculate the amount of lumens you will need for any room, which is becoming a more important calculation due to the increasing popularity of LED fixtures.

A lumen is simply 1 unit of light output. LEDs are measured in lumens rather than wattage since LEDs put out a brighter light, without using a lot of wattage. For example, a 5 Watt LED can be the same amount of light as a 40 Watt Incandescent bulb. They put out the same amount of light (lumens), but the LED uses significantly less power.

It is important to keep in mind, that not all LEDs are the same when comparing by the wattage. You have to factor in lumen output and color temperature as well. We will dive into the ins and outs of LEDs in another post, but for now, let’s see how to calculate the lumens for any room.

To calculate the lumens required to light the same room we used in our earlier post, just multiply the square feet of the room by the lumens per square foot required for the room type. Our room example is a living room which requires 15 lumens per square foot.

To get the square footage, all you need to do is multiply the length of the room in feet by the width of the room in feet. For example, a 16 foot long by 14 foot wide room has a square footage of 224. So we will multiply 224 by 15 and we get 3,360 lumens.

List of the required lumens per sq foot based on the room type:

  • Living Room - 15 Lumens
  • Kitchen General - 35 Lumens
  • Kitchen Task - 75 Lumens
  • Dining Room - 35 Lumens
  • Bedroom - 15 Lumens
  • Hallway - 10 Lumens
  • Bathroom - 75 Lumens

Notice the task orientated spaces will have a higher lumen requirement, like in the Kitchen and Bathroom. It is important to use a variety of light sources to achieve the higher lumen requirement for these rooms.

Using multiple sources of light in these task oriented rooms help in layering light. Having general lighting, task lighting, and accent lighting in each room is the key to achieve the best lighting possible.

In a bathroom, you can achieve the proper amount of task lighting with vanity lights above a mirror or wall sconces placed around the mirror. Also adding a chandelier or semi-flush ceiling mount light fixture will give the general lighting the room needs. Having more than one source of light is essential to achieve to proper lumens required.

Calculating the lumens needed to properly light each room in your home might seem like overkill but it really is the best way to ensure you have the adequate illumination to live, work, and play in your favorite spaces.

Still have questions or need advice on lighting your home? Contact us at 1-800-419-5967