To avoid these ads, REGISTER NOW!

watts = lumens

To avoid these ads, REGISTER NOW!

OldBarn

Banned
Joined
Dec 5, 2014
Messages
30
You can't do that. It depends on what type of lighting you are using. Every bulb is different.
 

alfredeneuman

Well-known member
Joined
Mar 3, 2011
Messages
4,584
Location
Fullerton, CA
There's no set watts to lumens ratio

It all depends on how efficient the light source is.
LED for example has a much higher efficiency than incandescent.
 
OP
A

akpolaris

Well-known member
Joined
Jun 14, 2010
Messages
214
Location
Seward, Ak
Then how do I figure what I need for 32' X 32' shop with 16' ceiling? I understood I was looking for 100 lumens/ sq ft. Is that correct?
 

BillK

Well-known member
Joined
Aug 24, 2006
Messages
9,348
Location
Beautiful Southern Maryland
ak,
If your shop is 32x32, that is 1024 sq ft. If you want 100 lumens per sq ft, you will need 102,400 lumens. Then you need to figure out what type of bulbs you are going to use and then you can figure out how many bulbs you need. I was looking at 6 tube T-8 fixtures the other day and I think they were around 18,000 lumens for each fixture. In your case you would divide 102,400 by 18,000 and get 5.68 so you would need 6 of those fixtures.

Does that help ?
 

BillK

Well-known member
Joined
Aug 24, 2006
Messages
9,348
Location
Beautiful Southern Maryland
Is 100 lumens/sf adequate for a shop?

****,
I think it should be. My shop is 1800 sq ft with 14ft ceilings and it has 6 2-tube 8ft T-12 fixtures. The T-12 bulbs are around 5000 lumens each so I have about 60,000 lumens for 1800 sq ft .... about 33 lumens per sq ft. It is workable with some task lighting but definitely needs to be brighter. I am looking at replacing the T-12 fixtures with 6 tube 4ft t-8s, about 18000 lumens per fixture. That is going to almost double the light to 60 lumens per sq ft. and should be more than enough.

My walls are painted white which makes a big difference too.
 
To avoid these ads, REGISTER NOW!

laser3kw

Well-known member
Joined
Nov 17, 2012
Messages
7,276
Location
northen IL
In my 30 x 40, I just installed 30 4ft t8 bulbs. The lights are above the 30 x 24 "work area" which has a 10ft ceiling. All walls and ceiling are painted white for best reflection. PLENTY of light
The lights are in 3rows- each row = 2, 8ft 4 bulb tandem fixtures and a 4ft 2 bulb fixture - 20ft total. == = == (bulb lay out per row)
 

CADPoint

Well-known member
Joined
Jan 31, 2011
Messages
155
Location
WSW of **** City
http://www.visual-3d.com/tools/interior/Default.aspx?id=14783

Go play with your layout and see what your lights will give you.

Most people don't understand that most illumination presents itself
as a bubble of light and not as a complete spray of light.

One can note this on the bottom right of the web page of the light that you choose.

Below is what OSHA has set up as the minimum of lighting requirements for
various spaces.

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10630
 
OP
A

akpolaris

Well-known member
Joined
Jun 14, 2010
Messages
214
Location
Seward, Ak
This is a big help. The overhead lighting will be augmented with some specific task lights but this is a good start. thanks
 

LS6 Tommy

Well-known member
Joined
Dec 27, 2013
Messages
26,162
Location
Northern NJ
I don't mess with lighting enough to know the ratings/formulas/conversions, but the guys at plantedtank.net pretty much go crazy over the various "how much light for *** gallons/** inches of water depth" discussions. The ones deemed to be the lighting geniuses say it's now about PAR ratings. Lumens is "old tech" and watt rating questions send them right off the edge...:lol_hitti

Tommy
 
To avoid these ads, REGISTER NOW!
Top Bottom