Most rooms need one LED downlight for every 1.2 to 2 metres of ceiling, with the outer row half that distance from the walls. On a 2.4 m ceiling, that is usually 4 for a bedroom, 6 to 8 for a living room and 2 or 3 for a small bathroom. Ceiling height, beam angle and brightness change the count.
A spacing rule gets you close. For a specific room, check the count against lumens, the amount of light each fitting gives out.
How far apart should downlights be?
On a 2.4 m ceiling, downlights are usually spaced about 1.2 to 2 m apart, and the first row sits roughly half that distance in from the wall. Keeping the wall gap at half the spacing makes the light look even across the room rather than bunched in the middle. A wide beam, 60 degrees or more, spreads further and suits the wider end of the range. A narrow beam, often 40 degrees or less, makes tighter pools of light and needs closer spacing.
Higher ceilings let the beam spread further before it reaches the floor, so the spacing can open up. The trade-off is that the light is weaker by the time it lands, so a 2.7 m or 3 m ceiling often needs brighter fittings rather than more of them. On raked or very high ceilings, pendants or wall lights often do the job better than downlights.
How many downlights for each room?
These counts are a starting point for typical rooms with 2.4 m ceilings and wide-beam LED downlights of about 700 to 900 lumens. Darker paint, timber floors or a room used for close work will push the number up. A pale room that also has lamps or pendants will need fewer.
| Room | Typical size | Typical downlights |
|---|---|---|
| Bedroom | 3.5 m x 3.5 m | 4, often on a dimmer |
| Living room | 5 m x 4 m | 6 to 8, with lamps or pendants as a second layer |
| Kitchen | 4 m x 3 m | 4 to 6, placed over the benches rather than the middle of the floor |
| Bathroom | 2.5 m x 2 m | 2 or 3, plus a light at the mirror |
| Hallway | 1 m wide | 1 every 1.5 to 2 m of length |
| Laundry | 2 m x 2 m | 1 or 2 |
How do you work out downlights with lumens?
Multiply the room's floor area by the light level you want, in lux, then divide by the lumens of one downlight. Lux is light per square metre at the surface, so a 16 m² room lit to 150 lux needs about 2,400 lumens arriving at the floor. With 800-lumen downlights, that is three fittings on paper.
In practice some light is lost to the walls and ceiling, so electricians and lighting designers add a margin, often 20 to 30 percent, and then round up to a number that spaces evenly. The 16 m² room above ends up with four downlights in a two-by-two grid. These are the light levels commonly used as a guide in homes:
| Area | Typical light level | Why |
|---|---|---|
| Hallways and stairs | About 50 to 100 lux | Enough to move around safely |
| Bedrooms and living rooms | About 100 to 150 lux | General light, usually dimmed down in the evening |
| Bathrooms | About 150 to 200 lux | Brighter at the mirror for shaving and make-up |
| Kitchen benches and study desks | About 300 to 400 lux | Task light for cutting, reading and close work |
The lumens figure is on the box or the spec sheet. Ignore the wattage when comparing LED downlights, because two 10 W fittings can give out quite different amounts of light.
Where should downlights go in a kitchen?
In a kitchen, put the downlights over the benches, not in the centre of the room. A light behind you throws your shadow across the bench while you work. Placing a row roughly above the front edge of the bench, often 400 to 600 mm out from the wall cabinets, lights the work surface instead. Island benches usually get their own row or a set of pendants. Under-cabinet LED strip fills the gap under overhead cupboards that ceiling downlights cannot reach.
Planning new downlights?
DM Electrical can lay out the lighting room by room, choose fittings and dimmers that work together, and install and certify the work. Based in Brookvale, licensed and Level 2 ASP accredited, across the Northern Beaches and greater Sydney.
Can you have too many downlights?
Yes. Too many downlights make a room glary and flat, and every one is a hole in the ceiling. A grid of lights all at full brightness lights the floor evenly but leaves the walls and corners dull, which makes a room feel smaller. A layered plan usually looks better: fewer downlights for general light, plus pendants, wall lights or lamps where people sit and read.
Each downlight also cuts through the ceiling insulation. Fittings rated IC-4 can be covered by insulation, so the gap stays small, while older fittings that need clearance leave a bare patch around every light. On a new install, IC-4 rated downlights are worth asking for.
What colour temperature should downlights be?
Warm white, around 3000K, suits living rooms and bedrooms, and a neutral 4000K suits kitchens, laundries and bathrooms where you want to see clearly. Mixing colours in one open-plan space tends to look patchy, so pick one for each zone. If you want to dim them, the dimmer and driver have to match, or the lights can buzz or flicker. Our guide to why LED downlights flicker explains what to check.
Do downlights in a bathroom have special rules?
Yes. A downlight over a shower or bath sits in a wet-area zone and needs a fitting rated for it, usually at least IPX4. Our guide to bathroom electrical zones shows which ratings each zone needs. Fitting a downlight, moving one or adding a new circuit is electrical work, and in NSW only a licensed electrician can do it. The electrician tests the work and gives you a Certificate of Compliance for Electrical Work.
Frequently asked questions
How many downlights do I need for a 4 x 4 m room?
A 4 m x 4 m room with a 2.4 m ceiling usually needs four wide-beam LED downlights of about 800 lumens, set out in a two-by-two grid about 2 m apart and 1 m in from each wall. Add one or two more if the room is dark or used for close work, or fewer if lamps and pendants also light it.
How far should downlights be from the wall?
About half the distance between the downlights. If they are spaced 1.6 m apart, the first row sits around 0.8 m from the wall. Closer than about 0.5 m can create bright scallops of light on the wall, which some people like on feature walls and others find distracting.
How many lumens should a downlight be?
Most LED downlights for homes give out about 600 to 1,000 lumens. Around 700 to 900 lumens suits general lighting in bedrooms and living rooms on a 2.4 m ceiling. Kitchens and higher ceilings often call for the brighter end, or for a few extra fittings.
Can I replace old halogen downlights with LED?
Yes, and it usually cuts the lighting power used by a large margin. Older 12 V halogen downlights run from a transformer, so a licensed electrician normally removes the transformer and fits a complete LED downlight with its own driver. This is also a good time to switch to IC-4 rated fittings so the insulation can go back over them.
The bottom line
For most rooms, space downlights about 1.2 to 2 m apart, keep the outer row half that distance from the walls, and check the count against the room's area and the lumens of the fittings. Put kitchen lights over the benches, add a second layer of lighting in living areas, and choose IC-4 rated fittings. Our residential electricians plan and install lighting across the Northern Beaches and greater Sydney. Get in touch before the rough-in.