Spacing of down-lights for even illumination

[paddypower]

Is there a magic formula for spacing down-lights to give an even light? I’m supplementing and giving an alternative to existing lighting by putting 4 down-lights into a 15’ X 12’ room. I was just going to space them evenly but thought this may give more light to the centre than the edge of the room.

regards

 

[Steve]

downlights are tricky - especially with low ceilings. If you want to work out the area covered by each light, i think some simple trigonometry would do the job - based on the stated angle of the bulb's beam and the distance to the floor.

4 downlights will give 4 pools of light in a room that size. However, if you want more even light distribution, use GU10 fluorescent lamps. They are about 2-3 times the price of regular ones (£5.99 at maplin) but they will last longer and give a much cleaner, better light than a halogen, and the beam is wider (I saw some in action, and they dont really have a beam as such). Only drawback is you cant dim them.

 

[paddypower]

Thanks crafty,
not much good at trig! Have drawn it out on graph paper and by having 3 evenly spaced lines going across the room and ignoring the middle one, the remaining 4 intersection would appear to give an even spread. I hadn't heard of 'GU10 fluorescent lamps' but they sound ideal.

 

[breezer]

I hadn't heard of 'GU10 fluorescent lamps' but they sound ideal.

available form all good wholesalers / lamp stockists

 

[Steve]

looking at those, your offering looks like it would be brighter, breezer, but they both claim to be the same wattage.

by the way, Maplin's have gone up to £7.99 now. IIRC, they were in the sale before.

 

[ABN]

Can't find the site where I saw a review on these or similar ones.

The users comments where that they are too big and stick out rather than being flush with the mounting as a normal GU10 does so take care before ordering