How many Downlights do I need

[plugy]

Afternoon all,

we are trying to work out how many down lights we need for our new extension. We have looked at various websites but get conflicting information.

The room is approximately 11ft X 15ft with a height of 7ft, the room has a steel across the center to support the joists.

We have been told we need approximately 180 - 200 watts of light. Then rule of thumb half your ceiling height to give the spacing for each downright, so would be 3.5 feet apart. Placing them 1.5-2ft from the edge of the room. This would equate to around 9 lights each side? at an average of 5w giving 45w of LED light, equivalent to 260watts of light.

Is this about right? 18 down lights at 5w each, is this overkill or not enough. we are planning on dimmable ones so if a ittle bright we should be able to control it.

Any help/suggestions would be appreciated.

 

[oldbutnotdead]

3 suggestions for you;
1 Search in the Electrics forum, this isn't really a new topic
2 Post in the Electrics forum if your searches don't produce anything useful
3 Don't do downlights. Your ceilings are too low, you'll get really irritaring glare when you're sat in the chair or trying to watch the telly. A central fitting (not a pendant, you'll hit your head on it) will do for most purposes, wall mounted uplights would give a nice effect (prob too late to get cabling in though), you can get freestanding uplights (Ikea do a nice one) which will also work well on a pale ceiling

 

[SFK]

Plugy,
Note that I have no issue with downlights, but do feel that they are better fo use in some rooms thane others - happy with bathrooms, not happy with them in living rooms.

Are you sure your room is only 11ft by 15ft (4m x 4.5m)? and you want to use 18 downlights?
I would have said that is far too many.
And 7ft ceiling is too low for downlights (their cone of light does not spread far enough).

In the olden days a 60W bulb would have illuminated that room.
And remember you will also have table lights.

So look at your other rooms and see what Wattage (or better lumins) of light you are using.
That will give you a ball park figure.

Down lights are terrible at lighting rooms, and do not know your room (windows etc) but as and example most large kitchens seem to be happy with 10 or so bulbs.
And your ceiling will not be so pock marked.

In summary, 18 is too many - suggest less than 10.
SFK

 

[Londoner2]

18 way too many, my extension is 4.5m x 5.6m and i have 9.

 

[A_Novice]

Our kitchen is 5m by 3.5m and we had 8 10w LEDs. Plenty.