How-to · UK domestic

How to hardwire LED tape lighting

LED tape is one of the most popular lighting upgrades in UK homes right now — under kitchen cabinets, along staircase stringers, inside alcoves. Doing it with a plug-in adapter works, but a hardwired installation looks cleaner and lasts longer. The mains side of the job is Part P work, but if a spur is already in place, connecting the driver and the tape is something a careful DIYer can manage.

Helpful video reference. John Ward (jwflame) of Flameport Electrical in Poole, one of the most respected UK electrical educators on YouTube, covers LED tape in his video "LED Tape Part 1". He explains the range of tape types, driver options, controllers and aluminium channel in practical terms — worth watching before you buy anything, because choosing the right combination of tape and driver at the start saves a lot of trouble later.

Before you start. The mains side of this job — connecting a driver to an existing spur or lighting circuit — is notifiable work under Part P Building Regulations if it involves a new circuit or extends an existing one. If there is already a switched, fused spur in place, the low-voltage wiring from the driver to the tape is not Part P. If in doubt, call an electrician first. Either way, isolate the relevant lighting circuit at the consumer unit and confirm dead with an approved voltage tester before touching any conductors.

1. Choose your LED tape and driver

There are two decisions to get right before you buy anything: voltage and wattage.

Most domestic LED tape runs on either 12 V DC or 24 V DC. For short runs under about 3 metres, 12 V works fine. For longer runs, 24 V keeps the brightness more even because the voltage drop along the tape is proportionally smaller. The driver and the tape must match — a 24 V driver on 12 V tape will destroy the tape immediately.

For wattage: add up the total wattage of your tape run (watts per metre multiplied by length) and choose a driver that exceeds that figure by at least 20 per cent. A driver running at maximum load runs hotter and fails sooner.

Colour-changing RGBW tape needs an RF or Wi-Fi controller between the driver and the tape, in addition to the driver itself. Single-colour tape connects directly to the driver output.

2. Isolate the circuit

Turn off the relevant lighting circuit at the consumer unit. If you are working from an existing switched fused spur, turn that off too. Confirm dead at the point you plan to connect, using an approved voltage tester — not a screwdriver with a neon bulb.

If there is no existing spur and you need a new mains connection run to where the driver will go, that is Part P work and needs an electrician or a self-certification from a competent person.

3. Plan the cable route

The mains side of the installation uses standard 1.0 mm twin and earth cable (brown live, blue neutral, bare earth sleeved green and yellow). Plan a route from the existing spur to where the driver will sit — typically inside a cabinet, in a ceiling void, or in a surface-mounted enclosure.

On the low-voltage side, keep the DC cable run from driver to tape as short and direct as possible. Voltage drop accumulates with length, and a long DC run to a 12 V tape can result in the far end being noticeably dimmer.

Keep mains cabling and low-voltage DC cabling separated where they run in parallel, particularly on dimmable systems where interference can cause flickering.

4. Fit the fused connection unit

A 3 A fused connection unit (FCU) provides the correct protection for the driver. Mount it in an accessible position so the fuse can be replaced if needed. In a bathroom, the FCU must be outside Zone 1 and outside the bathroom zones entirely for most configurations — the guide to bathroom electrical zones covers this in detail.

Connect the incoming mains supply to the supply-side terminals: brown to the L terminal, blue to N. The earth goes to the earth terminal in the FCU back box. Tighten all terminals firmly — loose connections in an FCU cause heat over time.

5. Wire the driver to the mains

On the load side of the FCU, connect brown to L and blue to N on the driver's mains input. Most LED drivers have clearly marked input and output terminals. Earth the driver enclosure if it has an earth terminal — a metal driver case that is not earthed becomes a hazard if the insulation inside fails.

Fix the driver in a ventilated position. LED drivers run warm under load. Fitting one inside a sealed box or directly against insulation shortens its life considerably. Most manufacturers specify a minimum clearance around the driver for airflow.

6. Connect the tape to the driver output

The driver output is low-voltage DC, typically labelled + and -. Connect the tape's positive wire to + and the negative to -. Getting this backwards will not damage the tape (it simply will not light up), but it is worth getting right first time.

Use push-in or solderless connectors rated for the width of tape you are using. Standard tape is 8 mm wide; high-output tape is often 10 mm or 12 mm wide, and the connectors are not interchangeable. Soldered joints are more reliable over the long term, but they are not necessary for a domestic installation if the connectors are correctly seated.

On a colour-changing system, connect the driver output to the controller input, then the controller output to the tape. Follow the controller manufacturer's wiring diagram — they vary between brands.

7. Fix the tape and test

LED tape has a self-adhesive backing, but on its own the backing is not reliable for permanent installations, particularly under heat from the driver or in kitchens. Aluminium channel holds the tape firmly, dissipates heat, and gives a clean finish with a diffuser cover. Press the tape into the channel before fitting the diffuser strip.

Once the tape is in place and all connections are made, restore power and check the run. A section that does not light almost always means a poor connector — reseat it, making sure the tape contacts align with the connector pins. A flickering section under a dimmer usually means the dimmer minimum load setting needs adjusting, or the driver is not dimmable and needs replacing with one that is.

Stop and call an electrician if: any mains connection feels warm to the touch after a short run; the FCU fuse blows repeatedly; the driver smells of burning; you find the existing spur has no earth conductor; or you are in any doubt about whether the existing circuit can support the additional load. LED tape draws very little current, but a poorly made connection at mains voltage is a fire risk regardless of the load it feeds.

When to call us

If you need a new mains circuit run to a kitchen, alcove or staircase for a lighting project, or if an existing spur turns out to be unprotected or incorrectly fused, that is a short job for a qualified electrician. Richard covers Sandwich and east Kent and is used to small domestic lighting jobs alongside larger rewire work.

Lighting circuit work in Sandwich?

Richard can run a new spur, check an existing one, or advise on the best way to feed a hardwired lighting project.

Contact Richard

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