Can I wire a second light from an existing ceiling rose myself?

Replacing or extending from an existing ceiling rose on the same circuit is generally exempt from Part P notification if you are just adding a connection at an existing accessory. However, running new cable through floors or joists, or adding a fan in a bathroom, moves into territory that most homeowners should have a qualified electrician check. If in doubt, get a professional opinion before you start.

What cable do I use for a fan that runs on the light switch?

A fan that runs whenever the light switch is on needs 1.0 mm twin and earth. Connect the brown to the switched live terminal and blue to the neutral. The fan comes on when the switch is operated and turns off when the switch is released.

What cable do I use for a bathroom fan with its own pull cord?

Use 1.0 mm three-core and earth. The three-core gives you a permanent live, a switched live (from the pull cord), and a neutral in one cable. This is needed so the fan can run independently of the room light.

How to Add a Spur from a Ceiling Rose for a Fan or Second Light (UK)

Helpful video reference. Gary at GSH Electrical's tutorial "How to Wire an Extractor Fan or a Second Light From a Ceiling Rose and Pendant" walks through the ceiling rose connections clearly. GSH Electrical is a UK electrical training channel based at Tresham College and their content is pitched correctly for UK installation practice.

Before you start. Turn off the lighting circuit at the consumer unit, not just the wall switch. Test dead at the ceiling rose using an approved voltage tester. If there are multiple cables coming into the rose and you are unsure which terminal is which — or if the cable colours are cloth, rubber or mixed old and new — stop and call a qualified electrician before going any further.

1. Isolate and confirm dead

Turn off the lighting circuit breaker at the consumer unit. In homes with a rewireable fuse box, pull the fuse cartridge and keep it in your pocket. Test the ceiling rose with a voltage tester at the terminals before removing the rose cover. Both the load side and supply side must read zero. If anything still reads live, go back to the board and check you have switched off the correct circuit.

2. Identify the ceiling rose terminal blocks

A UK ceiling rose typically has three separate terminal blocks. The central block takes the incoming mains supply (line in, neutral in). The outer block(s) handle the loop — supply feeds through to the next rose on the circuit. The switch wire terminal connects the switched live and neutral going down to the wall switch. Take a clear photo before touching any conductors. If the rose is an older type with only two blocks, or everything appears joined with chocolate connectors, you may be dealing with a junction box circuit — check the layout before proceeding.

3. Choose the right cable for the job

For a fan or light that runs whenever the existing room light is on, you need 1.0 mm two-core and earth (twin and earth, T&E). Connect to the switched live and neutral — the fan comes on with the light and runs until the switch goes off. For a fan or light controlled by its own switch (for example, a separate pull cord in a bathroom), you need 1.0 mm three-core and earth. Three-core lets you carry the live feed, the switched live back from the new switch, and a neutral — all in one cable. If in doubt, fit three-core: it covers both scenarios.

4. Run the new cable safely

Plan the cable route before lifting anything. Cables in walls must run in a prescribed zone — vertically from the fitting or horizontally to the switch — so a future drill or screw does not hit them. Above a ceiling is a relatively protected route. Fix the cable with appropriate clips at the intervals required by BS 7671. If the cable passes through any joist holes, use grommets to protect the insulation from the wood edge.

5. Connect at the ceiling rose

In a loop-in ceiling rose the connection is made at three terminal blocks. Take the new cable into the rose through a fresh entry hole. Connect the brown conductor to the switched-live terminal block (the one the switch cable's brown core is already connected to). Connect the blue neutral to the neutral terminal block. Sleeve the bare earth in green-and-yellow sleeving and connect it to the earth terminal or fix it to the back box. Do not overtighten push-fit terminals — seat the conductor fully until it clicks. Wagos or legacy push connectors should click audibly.

6. Wire the fan or second light fitting

At the fan end, connect brown to the L (line) terminal, blue to N (neutral), and the sleeved earth to the earth terminal on the fan body. Check the manufacturer's wiring diagram — some fans with overrun timers have a separate live-in and a switched-live terminal, and mixing the two will prevent the timer working. For a second light fitting, connect brown to the switched live, blue to neutral, and earth to the fitting body if it is metal. The flex suspension point should carry no cable weight.

7. Restore power and test

Refit the ceiling rose cover, making sure no conductors are trapped. Go back to the consumer unit and restore the circuit. Test the light switch. If the new fan or light does not operate, check first that the connection at the rose is secure. If the RCD or MCB trips immediately, switch off again and check for any conductor touching an earth terminal it should not.

Stop and call an electrician if: you find more cables in the ceiling rose than you expected and cannot identify which block is which; the cable colours are pre-2004 red and black and you are unsure how they relate to the new wiring; there is no earth at the ceiling rose; or the circuit keeps tripping after your connections are made.

When to call us

Taking a spur from a ceiling rose is a job a careful homeowner can tackle when it is a straightforward loop-in rose in good condition. Add a new cable run through joists or a partition wall, or encounter anything that does not match the description above, and it is worth a call. Richard covers Sandwich and east Kent on small local jobs at the £10 per 10-minute rate.

Need lighting work in Sandwich?

Richard handles ceiling rose connections, extra light fittings and fan installations across east Kent as small local jobs.

Contact Richard

How to add an extractor fan or second light from an existing ceiling rose