How to install under-cupboard LED strip lights in a kitchen

Helpful video reference. Ben Poulter's September 2025 walkthrough on the Toolbox Talks for Electricians channel gets the UK-specific parts right: hardwiring from the kitchen circuit via a fused spur, using aluminium profiles with diffusers, and positioning the strip 30-50 mm back from the front edge of the unit to avoid glare. Worth watching before you start measuring up.

1. Plan your layout

Measure the underside of each wall unit you want to light and draw a rough sketch of where the LED profiles will sit. Decide where the LED driver will be hidden (inside the end unit is common) and where the local switch will go. Note the cable route from the fused connection unit to the driver.

A single run of 24 V LED strip at 14 W per metre rarely draws more than 0.5 A total, so a single FCU with a 3 A fuse cartridge is more than adequate for a run covering four to six standard 600 mm wall units. If you are lighting a very long run or adding a second row, calculate the total wattage and check the driver's output rating before ordering.

2. Fix the aluminium profiles

Cut each profile section to the length of the wall unit using a junior hacksaw or mitre box. A clean cut matters here because the diffuser clips into the profile ends and a ragged edge will stop it sitting flush.

Position each profile 30-50 mm back from the front edge of the unit base. Any closer and the light source will be visible from a seated position at the table, causing glare. Any further back and the light cone misses the front section of the worktop.

Fix through the base of the unit with short M3 or 3.5 mm wood screws. Two screws per 600 mm section is sufficient. Run a bead of clear silicone along the back of the profile before fixing if you want to limit condensation ingress around the hob area.

3. Isolate the kitchen circuit at the consumer unit

Find the MCB or RCBO that feeds the kitchen sockets. Switch it off. Tape over the switch or lock the consumer unit door to prevent accidental re-energisation while you work.

Go to the socket position where you plan to fit the fused connection unit. Test the terminals with a non-contact voltage tester or a proper voltage indicator. Both poles must be dead before you unscrew anything.

4. Run the supply cable

Route 1.0 mm² two-core-and-earth cable from the FCU position to the LED driver location. Clip the cable at 250 mm intervals along the back of the units using white oval cable clips, or run it through a length of mini-trunking if you want a neater finish inside the units.

Terminate the cable at the driver end but do not connect it yet. Leave a tail of 200 mm to work with. Sleeve the earth with green-and-yellow sleeving if it does not already have one.

5. Wire the fused connection unit

A fused connection unit (FCU) gives you a local means of isolation and the 3 A fuse protects the cable feeding the LED driver. You can spur off a socket on the ring final using a junction box behind the socket, or fit the FCU in place of an existing socket and connect it to the ring using a junction box inside the unit.

Connect line (brown) and neutral (blue) into the FCU's load terminals and the earth to the earth terminal. Fit a 3 A BS 1362 fuse cartridge. Do not use a 13 A fuse for LED lighting: if there is a fault on the flex between the FCU and the driver, a 13 A fuse will not protect it.

If the FCU has a neon indicator or a rocker switch, this doubles as the kitchen lights switch. Alternatively, wire through a separate pattress with an inline switch on the driver side.

6. Connect the LED driver

The LED driver is what converts 230 V mains to the low-voltage DC output the strip needs. Most 24 V constant-voltage drivers have screw-terminal mains input blocks labelled L, N and earth, and a separate output block labelled V+ and V-.

Connect the supply cable (line, neutral, earth) into the mains input block. Connect the low-voltage output leads to the wiring that runs to the strip connectors. Use the driver's own screw terminals rather than chocolate-block connectors for the mains input side.

Mount the driver inside the end wall unit using the keyhole slots on its base. Do not enclose it completely: drivers generate some heat and need a small amount of airspace. A gap of 20 mm above the driver is sufficient for a domestic installation.

7. Load the strip and fit diffusers

Peel the self-adhesive backing and press the LED strip into the profile channel. Work from one end to the other and press firmly along the full length so no sections lift. Cut the strip only at the marked cut lines (typically every 50 mm on 12 V strip, every 100 mm on 24 V) using scissors or a sharp craft knife.

Use quick-clip push-in connectors at the strip-to-driver junction if you are not confident soldering. Make sure the polarity arrows on the connector match the strip markings: LED strip is polarity-sensitive and will simply not light if connected backwards.

Snap the diffuser covers into the profile and fit the end caps. The diffusers spread the point sources so the light appears as a continuous line rather than a row of dots, and they reduce UV degradation of the adhesive tape over time.

8. Restore power and test

Switch the kitchen circuit back on at the consumer unit. Operate the FCU or inline switch. All sections should illuminate evenly. Walk along the worktop and check for any dark spots at profile joints: these usually mean a connector has not clicked home properly.

Check that the FCU does not feel warm after 10 minutes of operation. Some warmth in the driver body is normal; a hot FCU or a burning smell is not.

When to call us

The electrical work on under-cupboard lighting is modest, but it sits notifiable under Part P if it involves adding a new circuit. Spuring off an existing ring final or radial via an FCU is not notifiable, so most kitchen LED strip jobs fall outside the notification requirement. If you are in any doubt, or if the job turns out to involve more cable than expected, call. Small local jobs in Sandwich are £10 per 10 minutes.