Log in

View Full Version : Calculate 5900sq. Feet for lighting


rodriv
Jun 11, 2010, 06:55 AM
Four walls 5900 sq. feet how much lighting do I need?

jpbuzzworthy
Jun 11, 2010, 07:16 AM
Depends on how much Light you want.



Lumens per square foot, also known as a footcandle, is the measurement used to determine how much light an area is receiving. To calculate it, you need to calculate the area and the total amount of light. It is commonly used in homes to determine how much light is needed in different areas. For example, while 7.5 lumens per square foot might be sufficient for a hallway, you would probably want 35 lumens per square foot for a kitchen.


1.
Step 1

Determine the square footage of the area that you are lighting. You know this.
2.
Step 2

Determine the total lighting power in the area by adding the number of lumens for each bulb. The number of lumens will be listed in the manufacturer's information for the light bulb and you need to decide which type of lighting you will use so you can then get this info.
3.
Step 3

Divide the number of lumens generated, found in Step 2, by the square footage of the area lit, found in Step 1, to calculate lumens per square foot. For example, if you had a 135 square foot bedroom lit by a total of 2,025 lumens, you would have 15 lumens per square foot.


Something that can trip you up is the height of the ceilings. Where I got this information, I'm betting it for residential application with average ceiling height. If you have higher ceilings, like it's a warehouse or something you may want to go to the high side of the calculations.

tkrussell
Jun 12, 2010, 05:22 AM
The answer given is a very basic calculation based on already knowing several factors that have not been determined.


four walls 5900 sq. feet how much lighting do I need?

What will be the task?

What is the purpose of the space?

An office area may need 50 to 80 footcandles at task level of 30 inch above floor.

A retail space may need 80 to 100 footcandles.

A warehouse may need only 20 to 30 foot candles.

Need to define the purpose of the space, the task that will be performed, the age of the occupants, the reflectance of the surfaces to include ceilings, walls and floors, obstacles, color of surfaces, what type of lighting fixtures and sources to be used to, what are the efficiency factors of the chosen lighting fixtures, ceiling height of the space.

First question is what is the purpose of the space.