Short answer
Spotlights in a ceiling with insulation above must be suitable for covering, otherwise they overheat. A fire-rated ceiling needs a spotlight that does not compromise the fire resistance, or a fire-rated hood around it. For an average room, allow one spotlight per one and a half to two square metres, depending on the light output.
Who this article is for Anyone who wants spotlights in a living room, kitchen or bathroom. Cutting into a ceiling is doable; what is above it decides whether it is wise.
Insulation is the first point
A spotlight produces heat, LED too. If insulation is packed tightly around it, that heat has nowhere to go. The driver then fails sooner and in the worst case the timber above discolours.
So look for the marking that a spotlight may be covered. If it may not, there must be space around it, and that is hard to guarantee in an insulated ceiling.
Fire resistance
A ceiling can be part of a fire separation, for example between a garage and the house or between two homes. Making a hole in it compromises that. Then it needs a spotlight assessed for that purpose, or a fire-rated hood around it.
This is exactly the point that gets skipped in DIY fitting, and that an insurer does look at when there is damage.
How many spotlights
Rule of thumb for a living room with spotlights as the main lighting: one spotlight per one and a half to two square metres. Closer together above the worktop in a kitchen, further apart in a bedroom.
More important than the number is the placement: do not shine into your own eyes from the sofa, and above the worktop set them slightly forward so you are not standing in your own shadow.
Drivers
Every LED spotlight has a driver. Three options:
If you cannot get to it later, choose spotlights with the driver built in.
- in the spotlight: simple, but if it fails you replace the whole spotlight
- separate per spotlight: above the ceiling, keep it accessible
- central for a group of spotlights: neat, but all spotlights go out if the driver fails
With a suspended ceiling or a hatch, separate is fine. If you cannot get to it later, choose spotlights with the driver built in.
Dimming
If you want to dim, choose spotlights and a dimmer that go together, and do not mix brands. Why that goes wrong is explained in dimming LEDs.
In the bathroom
The zone rules apply there, so a protection rating that suits the location. What is allowed where is explained in electrics in the bathroom.
From my own work
In a loft in Geleen the previous occupant had fitted spotlights in an insulated ceiling, with the insulation wool stuffed tightly around them. Two had already burnt out and the wooden beam above was discoloured. Replaced with spotlights that may be covered, at the right distance from the insulation, and the problem was gone for good.
When to call an electrician
- Spotlights are going into a ceiling with insulation or into a fire separation
- Spotlights fail regularly or the ceiling gets warm
- You want to know how many spotlights a room needs
I look at the ceiling before anything is cut. Request a quote.
Frequently asked questions
Can spotlights go in an insulated ceiling?
Only if they are suitable for covering. Otherwise they overheat and in time the timber above discolours.
How many spotlights do I need?
Rule of thumb: one spotlight per one and a half to two square metres if they are the main lighting. Closer together above a worktop.
Where should the driver go?
In the spotlight if you cannot get to it later, separately above it if there is a hatch or a suspended ceiling.
Further reading
Installing outdoor lighting: what goes on underground
The light is the fun part, the cable the most important. Lay an empty duct now and you can extend later without digging.
The light is not working: check it yourself in four steps
Nine times out of ten it is the bulb, the lampholder or the switch. The tenth time it is a connection, and then you call.
Dimming LEDs: why they flicker, buzz or do not switch off
Almost every LED dimming problem comes from a dimmer made for incandescent bulbs. A new dimmer solves it.
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