LED Downlights: The Complete Buying Guide
LED downlights are the workhorse of modern Australian lighting. They sit flush in the ceiling, throw clean, even light across a room, and sip a fraction of the power of the halogens they replaced. But the category has quietly become complex: cutout sizes, IC ratings, tri-colour switches, dimming protocols and beam angles all change how a fitting performs. This guide walks you through every decision so you can specify downlights with confidence, whether you're building, renovating or simply swapping out tired old fittings.
How to Choose LED Downlights
Good downlight selection comes down to matching the fitting to the ceiling it goes into and the job it has to do. Before you compare products, it helps to know a few things about your space: the ceiling construction, whether there's insulation above it, how high the ceiling is, the room's use, and whether you want to dim the lights. With those answers, the rest of the specification falls into place quickly. The sections below cover each factor in turn, and there's a checklist at the end to bring it all together.
Cutout Size: 70mm vs 90mm
The cutout is the hole your fitting drops into. It's the single most important measurement when replacing existing downlights, because a mismatch means patching plaster. In Australia the two most common cutouts are 70mm and 90mm, with 90mm being the everyday standard for homes.
A 90mm downlight suits general lighting in living areas, bedrooms, kitchens and hallways. The larger aperture accommodates a bigger LED and diffuser, which typically gives a broad, comfortable spread of light. A 70mm downlight is more compact and neat, often chosen for tighter spaces, feature areas or a more discreet ceiling look. If you're retrofitting, measure your existing hole before ordering. Many fittings are designed to cover minor variations, but it's always worth confirming the fitting's cutout range against your ceiling.
Fixed vs Gimbal (Tiltable) Downlights
A fixed downlight points straight down and is the right choice for general, even illumination. It's what you'll want across most of a ceiling grid.
A gimbal downlight (also called a tiltable or adjustable downlight) lets you angle the light. That's ideal for washing a feature wall, highlighting artwork or a splashback, or directing light in a raked ceiling. Many renovators use a mix: fixed fittings for ambient light and a few gimbals to accent the parts of a room they want to draw the eye to. If you have angled or cathedral ceilings, tiltable fittings are close to essential for aiming light where you actually need it. You can browse the gimble downlights range to see the adjustable options.
IC-4 Rating and Insulation Safety
This is a safety point worth taking seriously. If ceiling insulation (batts or blow-in) can come into contact with your downlights, the fitting must be rated to handle it. An IC rating means the fitting is designed so insulation can be installed right up against and over it without creating a fire risk or shortening the fitting's life.
You'll see ratings such as IC and IC-4 on modern LED downlights. Older halogen downlights ran hot and legally required clearance gaps in the insulation, which left cold spots and wasted energy. Insulation-contact-rated LED fittings remove that compromise. In insulated ceilings, always choose an appropriately rated fitting and follow the manufacturer's installation instructions. All electrical work and installation must be carried out by a licensed electrician.
IP Rating for Bathrooms and Wet Areas
The IP rating tells you how well a fitting resists dust and moisture. The two digits refer to solid-object protection and water protection respectively. For dry rooms this rarely matters, but bathrooms, ensuites, laundries and undercover outdoor areas have zones where a minimum IP rating applies.
As a rule of thumb, downlights over or near a shower or bath need a higher moisture rating than those in the rest of the room. When you're lighting a wet area, check the fitting's IP rating against the requirements for the zone it will sit in, and have your electrician confirm compliance. Choosing a suitably rated fitting protects both the light and the people using the room.
Colour Temperature and Tri-Colour CCT
Colour temperature, measured in Kelvin, sets the mood of a room. Warm white is cosy and relaxing and suits bedrooms and living rooms. Neutral white is clean and balanced and works well in kitchens and bathrooms. Cool white is bright and crisp and is often used in garages, laundries and task-heavy spaces.
Many LED downlights now offer tri-colour CCT, a small switch on the fitting that lets you select between warm, neutral and cool white at installation. This is genuinely useful: you can standardise on one product across the house and then tune each room, or change your mind later without buying new fittings. It also simplifies ordering, since you don't have to commit to a single colour temperature up front.
Dimmable and DALI Downlights
If you want to control light levels, choose dimmable LED downlights and pair them with a compatible dimmer. Not every LED fitting dims, and not every dimmer suits LEDs, so compatibility is key. Mismatched dimmers are the usual cause of flicker, buzzing or a narrow dimming range. Manufacturers publish compatibility guidance, and it's worth following it.
For larger homes, commercial fit-outs or anyone wanting smooth, reliable scene control, DALI is a professional dimming and control protocol that offers precise, flicker-free performance and integrates with building control systems. For most homes a quality trailing-edge dimmer paired with dimmable fittings does the job beautifully. If you're heading towards app or voice control, take a look at the smart downlights range.
Beam Angle
Beam angle describes how wide the light spreads from the fitting. A narrow beam concentrates light into a tighter pool, which is great for accenting or for very high ceilings where you want the light to reach the floor. A wider beam spreads light more broadly and is better for general room lighting and lower ceilings, giving softer overlap between fittings and fewer dark patches. Most general-purpose downlights use a wide beam for this reason. If in doubt for ambient lighting, wider is usually the safer choice.
Spacing and How Many Downlights You Need
There's no single magic number, but a reliable starting point ties spacing to ceiling height. A common guideline is to space fittings roughly evenly across the ceiling and keep them about half the ceiling height apart, then adjust for the room's purpose. Kitchens and bathrooms usually want more light and closer spacing; bedrooms and lounges can be more relaxed.
Keep these principles in mind:
- Work to the room, not a formula. Position fittings over the zones that need light, such as benches, sinks and reading areas.
- Avoid crowding the edges. Keep fittings a sensible distance from walls so you don't get harsh scalloping, unless you're deliberately washing a wall.
- Even is comfortable. Regular spacing prevents bright pools and dark gaps.
- Layer where it counts. Combine general downlights with accent gimbals or other fixtures in living spaces.
For an accurate plan, especially for open-plan or high-ceiling spaces, a lighting layout is worth doing before you buy. Our team can help you work through it.
Fixed vs Module Downlight Systems
Downlights broadly come two ways. An integrated (fixed) downlight is a single sealed unit where the LED, driver and housing are one piece; when it eventually reaches end of life you replace the whole fitting. These are simple, tidy and cost-effective.
A module system separates the light engine from the housing, so the LED module can be changed independently. This can make upgrades or changes easier down the track and offers flexibility across a project. For most homes an integrated fitting is perfectly suited; for larger builds or where future serviceability matters, a module system can be the smarter long-term choice.
Quick Buying Checklist
- Cutout size — measure your existing hole, or decide 70mm vs 90mm for a new install.
- Fixed or gimbal — fixed for general light, gimbal for accents and raked ceilings.
- IC / IC-4 rating — required wherever insulation contacts the fitting.
- IP rating — check the zone requirement for bathrooms and wet areas.
- Colour temperature — warm, neutral or cool; tri-colour CCT keeps your options open.
- Dimming — choose dimmable fittings and a compatible dimmer, or DALI for advanced control.
- Beam angle — wider for general light, narrower for accent or tall ceilings.
- Quantity and spacing — plan the layout to the room and ceiling height.
- Fitting type — integrated for simplicity, module system for serviceability.
- Brand and warranty — buy quality fittings backed by a solid warranty.
Frequently Asked Questions
What's the difference between a 70mm and 90mm downlight?
The number refers to the cutout, or the size of the hole the fitting sits in. 90mm is the everyday standard for general home lighting, while 70mm is a more compact option often used for a neater, more discreet look or tighter spaces. When replacing existing downlights, match your current cutout to avoid patching the ceiling.
Do LED downlights need to be IC rated?
If ceiling insulation can touch the fitting, yes. An IC or IC-4 rated downlight is designed to have insulation installed against and over it safely. This is the norm in insulated ceilings. Your licensed electrician can confirm what your installation requires.
Can I use LED downlights in a bathroom?
Yes, provided the fitting carries a suitable IP rating for the zone it's installed in. Areas over or near the shower and bath need better moisture protection than the rest of the room. Check the fitting's IP rating against the requirements for that zone and have your electrician confirm compliance.
Why do my LED downlights flicker when dimmed?
Flicker is almost always a compatibility issue between the LED fitting and the dimmer. Make sure the downlights are dimmable and that the dimmer is rated to work with them, following the manufacturer's compatibility guidance. Getting the pairing right removes the flicker.
What is tri-colour CCT?
Tri-colour CCT means the downlight has a switch that lets you select between warm, neutral and cool white at installation. It's a flexible feature that lets you tune the light to each room and keep the same fitting throughout the house.
Shop LED Downlights at Lights For You
We stock LED downlights from trusted lighting brands including SAL, Domus, Havit, Brilliant and CLA, covering everything from simple integrated fittings to tiltable gimbals and smart, controllable options. Browse the full range and shop LED downlights online with fast delivery Australia-wide. Prefer to see them in person or talk through a layout? Visit our showroom in Ashfield, Sydney, where our team can help you choose the right fittings for every room.
Shop LED Downlights at Lights For You
Browse our full LED Downlights range, or start with a few popular picks: