How to Install LED Strip Lights: A Step-by-Step Guide

To install LED strip lights, plan and measure the run, then choose a 12V or 24V strip with a matching plug-in power supply. Cut the strip only at its marked cut points and connect it with the right polarity while the supply is unplugged. Test it, then stick it to a clean surface or fit it into an aluminium profile. A low-voltage strip on a plug-in adapter is a DIY job; anything wired into your home's electrical installation needs a licensed electrical worker (LEW) in Singapore.

Key takeaways:

• The power supply must have the same voltage as the strip and enough wattage to spare; we recommend the strip uses no more than about 80% of the supply's rating.
• Cut only on the marked lines between the copper pads. Each strip has its own cut interval, from 2.5cm to 1m.
• Unplug the power supply before you make or change any connection, and test the strip before peeling the adhesive backing.
• Hardwiring a driver or strip, or adding a lighting point, is LEW work. We recommend not cutting or re-terminating 230V mains strips yourself.

What do you need to install LED strip lights?

You need the LED strip, a power supply (LED driver) with the same voltage as the strip, a way to join the wires (clip-on connectors or solder), and something to mount it with. Most strips have a self-adhesive backing; an aluminium profile with a diffuser gives a neater line of light and protects the strip.

• LED strip: 12V or 24V for most indoor uses, or a 230V strip for long outdoor runs.
• Power supply or driver rated for the strip's voltage and total wattage. For DIY, use one with a fitted plug and a SAFETY Mark.
• Connectors, extension wire, or a soldering iron and heat-shrink tubing.
• Sharp scissors, a measuring tape, and isopropyl alcohol or a dry cloth to clean the surface.
• Optional: aluminium profile or casing, mounting clips, a dimmer or remote controller made for LED strips.

Step 1: How do you plan and measure an LED strip installation?

Measure every stretch where the strip will go and add them up to get the total length. Then mark where the power supply will sit and where the nearest power point is, because the strip has to start near the supply. Sketch the layout first: it shows you where you need cuts, corners and extension wires before you buy anything.

Note whether the space is indoor and dry, or a wet or outdoor area, because that decides whether you need a waterproof (IP65) strip. If several separate stretches will share one supply, plan how the wires will run back to it.

Step 2: Should you choose a 12V, 24V or 230V LED strip?

Choose 12V for short runs such as cabinets and shelves, 24V for longer runs such as cove ceilings, and 230V only for long outdoor runs where a mains-powered strip makes sense. 12V and 24V strips run from a power supply and are the right choice for DIY. 230V strips run directly on mains voltage through their own mains power lead, so cutting and re-terminating them exposes mains conductors. We recommend buying them in the length you need and having any cutting or re-termination done by an LEW; hardwiring a 230V strip into your electrical installation must be done by an LEW.

Prices are our website prices in November 2026 and may change; check each product page for the current price. COB strips have 480 LEDs per metre, so they give a smooth, dot-free line, while SMD strips show separate points of light unless you use a diffuser.

Step 3: How do you choose the right power supply for an LED strip?

Pick a power supply with the same output voltage as the strip and a wattage rating above the strip's total load. Work out the strip's total wattage (watts per metre times length), then check the supply's datasheet for how close to its rating it may run. As a simple rule we recommend sizing the supply so the strip uses no more than about 80% of its rating, which means dividing the strip's wattage by 0.8.

Datasheets matter because supplies differ. Power supply maker MEAN WELL notes in its LED driver FAQ that most general AC/DC power supplies are suggested for use at about 70% load, while its LED drivers can run at full load as long as they stay within the working temperature in the datasheet. Two worked examples with our strips, using the 80% rule:

• A 12V COB strip, 5m at 11W/m, draws 55W. 55 divided by 0.8 is about 69W, so choose a 12V supply rated 70W or more.
• A 24V COB strip, 10m at 11W/m, draws 110W. 110 divided by 0.8 is about 138W, so choose a 24V supply rated 138W or more, such as 150W.

A full 10m reel is a lot of current to send through one end of a strip. Our advice: for anything over about 5m, use 24V rather than 12V, and feed power at both ends or from the middle of a long run so the far end does not run dim.

Most strips use a constant voltage supply. If you want to dim the strip, the supply or controller must be made for dimming. Our guide What Is an LED Driver? covers constant voltage versus constant current, dimming and the SAFETY Mark that LED drivers sold in Singapore must carry under the CPSO controlled goods list.

Step 4: Where can you cut an LED strip?

Cut an LED strip only on the marked cut lines, which run across the middle of the small copper pads between sections. Cutting anywhere else breaks a circuit and the last section will not light. The cut interval is printed on the strip and listed in the specs: our SMD 2835 strip cuts every 2.5cm, the COB and SMD 5050 strips every 5cm, and the 230V strips only every 1m. Always go by the marks on your own reel.

Cut cleanly with sharp scissors, then keep the off-cut: you can power it as a separate piece with its own connector. Every separate piece has to be wired back to a power supply, so avoid cuts you do not need. We recommend not cutting 230V strips yourself: a cut mains strip must be terminated and sealed properly before it is powered, so have an LEW do it.

Step 5: How do you connect LED strips together and to the power supply?

Join pieces with clip-on connectors that grip the copper pads, or solder wires to the pads, with the power supply unplugged. Polarity matters: the pads are marked + and -, and the positive wire (usually red) must go to + and the negative wire (usually black) to -. If a strip stays dark after connecting, check the polarity first.

1. Unplug the power supply before making or changing any connection.
2. Open the connector, slide the strip end in so the pads sit under the contacts, and close it firmly.
3. For corners, use an L-shaped connector or a short extension wire between two pieces. Keep the wire between the supply and the strip as short as practical.
4. Plug the strip's DC lead into the power supply's DC output plug.
5. For RGB or tunable white strips, connect the strip to its controller first, then the controller to the supply.

For DIY, use a power supply with a fitted mains plug. Drivers with screw terminals for the mains input are hardwired into your electrical installation and must be connected by an LEW. Check clip-on connectors are fully closed; for runs you cannot reach later, such as inside a cove, soldered joints are the more secure choice.

Step 6: Why should you test the strip before sticking it?

Testing first catches a reversed connection, a bad cut or a loose connector while the strip is still easy to move, so switch the whole setup on before you peel the adhesive backing. Once the backing is off and the strip is pressed down, it usually cannot be lifted and stuck again cleanly.

Step 7: How do you mount LED strip lights so they stay up?

Clean the surface with isopropyl alcohol or a dry cloth, let it dry, then peel the backing a little at a time and press the strip down with your fingers as you go. Rough, dusty or painted surfaces hold adhesive poorly; use mounting clips or an aluminium profile there.

An aluminium profile (also called an LED strip casing or channel) is the neatest option. The strip sticks inside the channel, a diffuser cover hides the individual LEDs, and the metal helps carry heat away from the strip. Bend strips gently around corners and do not fold them sharply across the LEDs.

How do you install LED strip lights on a ceiling?

For a ceiling cove, the strip sits on the top ledge of a false ceiling box or an L-shaped pelmet and shines upwards onto the ceiling, so you see a soft glow without seeing the strip. Use a 24V strip for long coves, a COB strip if you want a seamless line, and place the power supply where it can be reached later, such as next to an access panel. Do not bury the supply in insulation or seal it in an unventilated box; it needs airflow to stay cool.

• Keep the strip far enough back from the edge of the ledge that it is hidden from where people sit or stand.
• Run long coves in sections, each fed by its own wire from the supply, rather than one very long strip.
• A cove driver connected to your home wiring and switched from a wall switch is electrical installation work, so it must be done by an LEW.

For flats without a false ceiling, a surface aluminium profile fixed to the ceiling or the top of a wall cabinet gives a similar effect without building a cove. See our guide to types of LED lights for other ceiling options.

Can you install LED strip lights outdoors or in a bathroom?

Yes, with the right strip and with the power supply kept dry. Outdoors, use a waterproof strip rated IP65 or higher, such as our 24V COB waterproof strip, or for long runs our IP65 230V strips installed by an LEW. Keep a plug-in adapter indoors on an indoor socket; outdoor-rated drivers are normally hardwired, so have an LEW install them. Seal every cut end and connection with an end cap and sealant, since a cut IP65 strip is not waterproof until it is resealed.

In a bathroom, use only a 12V or 24V waterproof strip, such as our 12V SMD 5050 waterproof strip, keep the power supply outside the bathroom (in most homes that means a hardwired driver installed by an LEW), and keep the strip away from the shower and bath unless it and its fittings are rated for that zone. Do not use 230V strips in a bathroom. Any fixed wiring in a bathroom or outdoors is LEW work.

How do you replace an LED strip light?

Unplug the power supply, peel or lift the old strip out of its profile, and note its voltage, watts per metre, width and connector type. Fit a new strip with the same voltage and a width that suits the profile or connectors, check that the supply still covers the new strip's total wattage, then reconnect with the right polarity and test before sticking it down.

Do you need an electrician to install LED strip lights in Singapore?

Not for a low-voltage plug-in setup: a 12V or 24V strip on a plug-in adapter with a SAFETY Mark, matched to the strip, can be installed by anyone. You do need an LEW for any work on your electrical installation, such as hardwiring a driver to a lighting circuit, adding a new lighting point or connecting a strip to a wall switch. The Energy Market Authority explains when to engage a licensed electrical worker.

Why is my LED strip dim at one end or flickering?

A strip that is dimmer at the far end is usually losing voltage along a long run. Feed power to both ends, split the run into shorter sections each wired to the supply, or use a 24V strip instead of 12V. Flickering usually points to an undersized or failing power supply, a loose connector, or a non-dimmable supply used with a dimmer.

• Check that the strip uses no more than about 80% of the supply's rated wattage.
• Re-seat or replace any clip-on connector that feels loose.
• Make sure the supply, dimmer and strip are all made for dimming if you dim the lights.

Where can you get LED strips and help in Singapore?

You can browse our LED strip lights, including COB, SMD, neon, waterproof and RGB strips, or visit our shop at Sim Lim Tower (about 123 LED Lighting). If you are not sure which strip, voltage or power supply fits your project, contact us with the length and location and we will help you choose.