Downlight spacing calculator

[SparkyAndGeorge]

Hi guys.
I was just browsing looking for any hints/tips on spacing for downlights and came across this useful calculator:

https://blog.recessedlighting.com/recessed-lighting-calculator/


Hope this is of some help to somebody.

 

[Taylortwocities]

Could be useful. the interesting thing is that the calculator gives no method of ceiling height.
IIRC the amount of light that arrives at floor level reduces with distance, so that must mean that more lights are needed for high ceilings.

 

[FatAlan]

Usually governed by trying to get a symmetrical spacing that fits with ceiling joists.
Obviously you get more technical when considering ceiling height, lumens and beam angles.

 

[Squid]

Useless, no accounting for chimney breasts, empty alcoves, built in alcoves etc etc.

 

[Octopus]

Why inches ??

 

[telectrix]

Why inches ??

because inches are civilised and can be understood by those of us who are over 40.

 

[Taylortwocities]

Why inches ??

It’s from one of our former colonies…Trumpland.

 

[telectrix]

who had the common sense to stick to feet/inches/yards/gallons when the UK was obsessed with euoro phile rubbish.

 

[Gavin John Hyde]

Of course the maths side of things works best when you got straight and flat walls. Seemingly a rarity. Otherwise what is mathematically accurate and spaced out well wont necessarily look aesthetically pleasing or accurate. you also have to factor the joists in to the marking out.
I have some thin MDF discs that i put some old chrome bezels on. when i am happy with the marking out, i stick these up with some little screws or double sided pads.
If I am happy then great, but I often get the customer to decide, and often move a few a couple of inches one way or another along the x or y axis, to get the visual effect