LED strip lighting is now the standard choice for under-cabinet kitchen illumination, cove and coffer lighting, stair nosing lights, and TV bias lighting — at lower running cost than fluorescent or halogen alternatives. Strips run at 12 V or 24 V DC, require a separate driver, and need a little planning around driver sizing, dimming compatibility, and IP rating near water.
Quality varies enormously. Getting the strip type, driver, dimmer, and mounting right is what separates a professional-looking installation that lasts years from one that flickers, overheats, or fades within months.
Strip Types: SMD2835, SMD5050, COB, and RGBW
The three-digit number after “SMD” (Surface Mount Device) refers to the chip footprint in tenths of a millimetre. SMD2835 chips are 2.8 mm × 3.5 mm; SMD5050 chips are 5.0 mm × 5.0 mm. COB (Chip-on-Board) bonds multiple LED dies directly onto a continuous substrate, producing a seamless line of light with no visible hot spots between chips.
| Strip type | Typical lumens/m | Chip / emitter width | Voltage | Best use | Approx. cost/m |
|---|---|---|---|---|---|
| SMD2835 | 400–600 lm/m | 2.8 mm | 12 V or 24 V | Under-cabinet, accent, cove | £3–£8 |
| SMD5050 | 600–900 lm/m | 5.0 mm | 12 V or 24 V | General ambient, ceiling coves | £6–£14 |
| COB | 800–1,500 lm/m | Continuous line | 24 V | Seamless linear lighting, display | £15–£30 |
| RGBW | 200–500 lm/m (white channel) | 5.0 mm (quad chip) | 12 V or 24 V | Colour-changing accent lighting | £8–£18 |
SMD2835 is the workhorse: efficient, cool-running, and available with CRI 90+ at the upper price point. SMD5050 chips carry three or four dies per package for higher output, though the dot effect is more pronounced at close range. RGBW strips use SMD5050-class quad chips to carry red, green, blue, and white dies together. COB strips produce a genuinely uniform line — the preferred choice where the strip or diffuser falls within the line of sight — and almost always run at 24 V.
IP Ratings and Where They Apply
IP (Ingress Protection) ratings describe resistance to dust and moisture. For LED strips, the relevant classifications are:
- IP20 — no moisture protection. Suitable for dry internal spaces only: living rooms, bedrooms, hallways, home offices. The most common type and the most affordable.
- IP44 — splash-proof. Suitable for bathroom Zone 2 (outside the bath/shower area, 0.6 m horizontally from the edge, up to 2.25 m height) and kitchen areas above splashback zones.
- IP65 — dust-tight with protection against low-pressure water jets. Appropriate for bathroom Zone 1 (directly above the bath or shower tray, to 2.25 m), outdoor covered areas, and garden lighting under a pergola or soffit. The silicone coating adds a slight amber tint to the light and reduces lumen output marginally.
- IP67 / IP68 — full submersion protection. Required for strip lights fitted directly into water features, pond edges, or external ground-level step lighting that will pool water.
[!warning] Bathroom zone compliance Under BS 7671 (the IET Wiring Regulations), Zone 0 is the interior of the bath or shower itself — no LED strip is suitable here regardless of rating. Zone 1 requires IPX4 minimum (IP44 or above). Any 240 V mains connections in zones 0 or 1 are prohibited; low-voltage (12 V or 24 V) supplies are permitted but the driver/transformer must be located outside both zones.
Colour Temperature
Colour temperature is measured in Kelvin (K). 2700 K (warm white) suits living rooms and bedrooms; 3000 K (soft white) is a versatile domestic mid-point; 4000 K (neutral white) works well in kitchens, bathrooms, and home offices; 6500 K (daylight) is used in photography and craft rooms but is rarely flattering in living spaces. RGBW and tuneable-white strips can dial through any range digitally. High-CRI (>90) strips at 2700–3000 K are worth specifying wherever food and skin tones need to render accurately.
Voltage: 12 V vs 24 V DC
All LED strips run on low-voltage DC — 12 V or 24 V — from a separate driver. 12 V is common and marginally cheaper but voltage drop becomes visible beyond about 3–4 m from the connection point. 24 V halves the current for the same wattage, allowing clean runs of 8–10 m. For any run over 3 m, or wherever COB strip is specified, 24 V is the right choice.
Driver and Transformer Sizing
An LED driver converts mains 230 V AC to the correct DC voltage and regulates current. “Transformer” is often used interchangeably in retail descriptions, though technically an LED driver is constant-current or constant-voltage regulated.
Wattage calculation: multiply the strip’s rated W/m by total length, then add 20%. Five metres of 12 W/m strip needs 5 × 12 = 60 W + 20% = 72 W minimum. Undersizing causes overheating, flickering, and early failure. Drivers are available as slim in-line units for ceiling voids and plinths, or surface-mount boxes; for dimmable installs the driver must be specified as dimmable and matched to the dimmer type.
Dimming Compatibility
Incorrect dimmer choice is the most common cause of LED strip flicker and premature driver failure.
Trailing-edge (electronic/RC) dimmers are compatible with most LED drivers and are the standard domestic choice for mains-side dimming. Leading-edge (“standard”) dimmers — designed for incandescent and halogen loads — frequently cause buzzing or incompatibility; always check the driver datasheet before specifying. 0–10 V or DALI dimming is used in commercial and high-end domestic installs: the driver accepts a separate low-voltage signal, giving very stable, flicker-free control.
PWM controllers (standard in smart and colour-changing systems) dim by rapidly switching the strip on and off. Below 1,000 Hz this produces visible flicker — uncomfortable for some people and problematic in spaces used for video or photography. Specify PWM frequencies of 1,000 Hz or above; 2,000 Hz or higher for media use.
Smart Controllers: RF, Bluetooth, and Zigbee
For RGBW or tuneable-white strips, a smart controller replaces the basic dimmer. RF controllers need no hub and work through walls but do not integrate with smart home platforms without a separate bridge. Bluetooth controllers pair directly with a phone app — easy to set up but range-limited to roughly 10 m with no remote access outside the home. Zigbee controllers connect to a smart home hub (compatible with common UK ecosystems), enabling scenes, automation, and voice control; they cost more upfront but are the most flexible long-term option.
Mounting: Self-Adhesive vs Aluminium Channel
Most strips ship with a 3M self-adhesive backing, which is adequate short-term on clean flat surfaces but weakens with heat cycling. Strips mounted directly on wood or plasterboard cannot dissipate heat, which degrades LED lifespan.
Aluminium channels (extrusions) are recommended for permanent installations. They provide mechanical retention and conduct heat away from the strip, maintaining junction temperature. A frosted PC diffuser clips into the channel and eliminates the dot effect between chips, producing a clean even line — particularly desirable with SMD strips in visible positions. Profiles are available in surface-mount, recessed (plasterboard-cut), corner-mount, and plinth/under-cabinet forms; budget £5–£15/m for channel plus diffuser.
Avoid folding strip at corners — use purpose-made corner connectors or cut at designated marks and rejoin with solder-free clip connectors.
UK Building Regulations and Electrical Safety
LED strip lighting at 12 V or 24 V DC is outside the scope of Part P when only the low-voltage side is being extended. However, connecting or replacing the driver is a 230 V mains connection and is notifiable under Part P in England and Wales — either notify Building Control or use a registered competent person scheme electrician. In kitchens, bathrooms, and external locations, any new mains circuit or addition to a circuit requires the same.
Bathroom zone compliance under BS 7671 applies regardless of notifiability. Locate drivers and all 230 V connections outside zones 0 and 1.
Common Applications
Under-cabinet kitchen lighting is the most popular domestic use. A run of 24 V SMD2835 or COB strip in a surface-mount aluminium channel under wall units provides shadow-free task lighting on the worktop; CRI 90+ at 3000–4000 K is the standard specification. Four to eight metres of strip typically suffices for an average kitchen.
Cove and coffer lighting bounces indirect light off a ceiling from a ledge or recess. The strip faces upward and is hidden; only the reflected glow is visible. COB strip or high-density SMD with a diffuser channel prevents scalloping on the ceiling.
Stair nosing lighting uses slim recessed profiles in each tread for orientation lighting without wall switches at every level. IP44 is advisable on internal stairs that are cleaned with damp mops.
TV backlighting (bias lighting) — typically 2–4 m of strip on the rear of the television panel — reduces eye strain in dark viewing rooms. A tuneable-white strip at 6500 K matches the D65 standard used in content mastering.
Typical 2026 UK Cost Ranges
| Item | Budget | Mid-range | Premium |
|---|---|---|---|
| Strip (per metre, supply only) | £3–£8 (SMD2835) | £8–£18 (SMD5050/RGBW) | £15–£30 (COB/high-CRI) |
| Aluminium channel with diffuser (per metre) | £5–£8 | £8–£12 | £10–£15 |
| LED driver (per unit) | £12–£20 | £20–£45 | £45–£90+ |
| Smart Zigbee controller | — | £25–£50 | £50–£100+ |
| Installation (electrician, per hour) | £50–£65 | £65–£80 | £80–£100+ |
A complete under-cabinet kitchen installation (6 m strip, channels, driver, trailing-edge dimmer, and electrician connection) typically costs £250–£500 supply and fit in 2026, depending on region and specification.
