The single decision that matters with LED strip lights is 24V or 230V — because 24V needs a driver and 230V doesn't. Get that right and the rest is length, colour temperature and where you hide the wire.
Get it wrong and you've either bought a strip that won't light, or a driver you didn't need and have nowhere to put.
We sell both across the counter at Villa Road every week, and the mistake we see most often isn't the strip at all. It's a driver bought to exactly the wattage of the run, with no headroom, quietly cooking itself in a cupboard.
Here's how to buy it properly.
1. First, know what you're actually buying
"LED strip lights" covers two quite different products, and the internet uses the phrase for both.
Flexible tape comes on a reel, has adhesive backing, and can be cut every few centimetres at marked points. It bends round corners. It's what most people picture.
Linkable rigid striplight comes in fixed lengths in an aluminium or polycarbonate housing, and links end-to-end with connectors. It doesn't bend, and it doesn't get cut — you build the run out of lengths instead.
What WME stocks is the second kind. That's a deliberate choice: rigid striplight in an aluminium housing sheds heat properly, keeps its brightness for longer, and doesn't peel off the underside of a cabinet in eighteen months when the adhesive gives up. If you specifically want reel tape, come and talk to us at the counter rather than ordering blind.
2. 24V or 230V — the decision everything else hangs off
230V striplight wires straight into your mains lighting circuit. No driver, no transformer, nothing extra. Simplest possible install.
24V striplight runs on extra-low voltage and needs a driver to step 230V down. That's an extra component, an extra box to hide, and an extra thing to size correctly.
So why would anyone choose 24V? Two reasons. It dims properly and smoothly, and it's safer to work around in tight, damp-ish spaces like the underside of a kitchen unit. If you want dimming, you want 24V.
The Knightsbridge LED5WCW is a 24V, 5W linkable flat striplight in cool white 6000K, putting out 580lm over 510mm, IP20, dimmable. Its smaller sibling the LED3WCW is 3W, 385lm, 310mm — useful for filling the short gap at the end of a run.
Trade Tip: don't mix 24V and 230V striplight in the same visual run. Even where both are the same nominal colour temperature, they're different products with different optics, and the join will show as a step in brightness the moment you switch them on. Pick one system per run and stick to it.
3. Sizing the driver — the bit that gets people
Add up the wattage of every strip on the run, then buy a driver rated comfortably above it. Not equal to it. Above it.
Six 5W strips is 30W of load. A 40W driver runs that happily. A 30W driver runs it at 100% continuously, gets hot, and dies early.
Trade Tip: leave yourself at least 20% headroom, and more if the driver is going somewhere with no airflow — a sealed plinth, the back of a cabinet, a loft. Drivers fail from heat far more often than they fail from age. The extra tenner on a bigger driver is the cheapest insurance in the job.
The Knightsbridge 24DC40 is a 24V 40W constant-voltage driver, IP20, 230V 50Hz. The range runs from the 24VDCA at 12W up through 24DC25D, 24DC50D, 24DC75 and 24DC100D — the "D" models are the dimmable ones.
Constant voltage is what strip lighting wants. If a driver says constant current, it's for something else.
4. Dimming: get it right at the driver
You cannot dim a non-dimmable driver by putting a dimmer switch in front of it. It'll flicker, buzz, or simply refuse.
Two workable routes. Either use a dimmable driver — the 24DC25D, 24DC50D or 24DC100D — with a compatible dimmer switch on the mains side. Or put an inline dimmer on the 24V side, after the driver.
The Knightsbridge LEDDIMMER is the inline option — 24V DC, works with flat and triangular strips, and has a memory function so it comes back on at the level you left it. For under-cabinet work it's usually the tidier answer, because the control sits where you actually use it.
5. Linking, splitting and joining
You build a run rather than cut one. Three parts do the work:
- LEDFCON — a 24V DC PVC connector, 33mm, for joining flat striplights end to end
- LED8SPLIT — an 8-way PVC splitter for 12/24V DC, when one driver feeds several separate runs
- LEDFCLIP — a stainless steel mounting clip, 33 x 30 x 6mm, two screws included
Use the clips. Double-sided tape on a rigid striplight is a job you'll do twice.
On cutting: flexible tape can be cut at its marked points and nowhere else — cut between them and you kill the segment. Linkable rigid striplight isn't cut at all. If you're 200mm short at the end of a worktop, that's what the 310mm 3W unit is for, not a hacksaw.
6. IP rating, and where our range stops
IP20 is indoor, dry, protected. That covers under-cabinet, shelving, plinths, cove lighting — the overwhelming majority of strip lighting jobs.
Outdoors, or inside a bathroom zone, you need a sealed strip and a sealed driver, and both have to be rated for it. A weatherproof strip fed by an IP20 driver sitting in a shed is not an outdoor installation; it's an indoor driver in a damp shed.
Being straight with you: every 24V driver we have in stock today is IP20. Our IP67 drivers are out of stock. So if you're lighting a garden, a porch or a wet room, ring us or come in before you order — we'll tell you what we can actually supply rather than sell you two-thirds of a job.
7. Colour temperature — pick before you buy, not after
Two numbers do almost all the work:
- 3000K warm white — yellower, softer. Living spaces, and kitchens where the units are wood or a warm colour.
- 4000K–6000K cool white — whiter and crisper. Task lighting, worktops, garages, utility rooms.
Under a worktop, most people prefer cooler; in a lounge alcove, most prefer warmer. There's no right answer, but there is a wrong one: mixing temperatures in the same sightline. Two runs 1000K apart in the same room look like a fault, not a choice.
If it's specifically a kitchen job you're planning, our under-cabinet lighting guide goes deeper on placement and shadow lines.
LED strip lights at a glance
| Question | 24V system | 230V system |
|---|---|---|
| Needs a driver? | Yes, constant voltage | No |
| Dims well? | Yes, with a dimmable driver or inline dimmer | Limited |
| Install complexity | Higher — driver needs a home | Lower |
| Best for | Under-cabinet, cove, anywhere dimming matters | Garages, utility, simple task runs |
| Driver sizing | Total load + 20% headroom minimum | N/A |
| Our stock IP rating | IP20 indoor (IP67 drivers currently out) | IP20 indoor |
Expert Help in the West Midlands
We've traded from Villa Road in Handsworth since 1975, and the counter is open to installers and homeowners alike.
Bring the measurement of the run and a photo of where the driver has to live. That's genuinely all we need to spec the whole thing — strip lengths, driver size, connectors and clips — in about five minutes, and we'll tell you honestly if what you want isn't something we can complete today.
Browse the range in LED Strip Lights, or come and see it lit.
Frequently asked questions
Can I cut LED strip lights to length?
Flexible tape, yes — but only at the marked cut points, and cutting anywhere else kills that segment. Linkable rigid striplight isn't cut at all; you build the run from fixed lengths and fill short gaps with a smaller unit.
What size driver do I need for LED strip lights?
Add up the wattage of every strip on the run and go at least 20% above it. Six 5W strips is 30W, so a 40W driver, not a 30W one. Drivers run permanently at full load fail early — especially in a sealed plinth or a loft with no airflow.
Why do my LED strip lights flicker when dimmed?
Almost always a driver that isn't dimmable, or a dimmer switch that isn't compatible with the driver. You can't dim a non-dimmable driver from the mains side. Use a dimmable driver with a matched dimmer, or fit an inline dimmer on the 24V side after the driver.