Choosing LED floodlight lumens and beam angle comes down to one question: how much light do you need on the ground, and over what area? Work out the area in square metres, pick a target lux level, calculate the lumens, then choose a beam angle that suits your mounting height. This guide walks through that method in metres and lux, for Australian homes, sheds and yards.
Lumens, lux, candela and beam angle in plain English
- Lumens (lm) are the total light a fitting produces in all directions.
- Lux (lx) is the light arriving on a surface. One lux is one lumen spread over one square metre.
- Candela (cd) is intensity in a single direction. It decides how far a beam reaches.
- Beam angle is the width of the cone where intensity stays at 50 per cent or more of the peak.
Watts only measure the electricity used. Two 50W floodlights can differ widely in output, so compare lumens, not watts. As a rough halogen equivalent, an old 500W halogen produced around 8,000 to 10,000 lumens, which a 60W to 100W LED can now match depending on its efficiency.
How lumens, beam angle and mounting height become lux
The same lumens spread over a bigger pool give lower lux. Take a 10,000 lumen floodlight with a 90 degree beam, mounted at 4 metres and aimed straight down. The light pool is 8 metres wide, or about 50 m². If we assume roughly 70 per cent of the output lands inside that pool (this varies by fitting), the average is about 140 lux.
Lift the same fitting to 8 metres and the pool grows to 16 metres wide, about 201 m². Average lux drops to around 35. Doubling the height quarters the light level.
Metric beam spread table by mounting height
Beam spread diameter = 2 x mounting height x tan (beam angle ÷ 2). The table below applies when the light is aimed straight down.
| Mounting height | 30 degrees | 60 degrees | 90 degrees | 120 degrees |
|---|---|---|---|---|
| 2.4 m | 1.3 m | 2.8 m | 4.8 m | 8.3 m |
| 3 m | 1.6 m | 3.5 m | 6.0 m | 10.4 m |
| 4 m | 2.1 m | 4.6 m | 8.0 m | 13.9 m |
| 6 m | 3.2 m | 6.9 m | 12.0 m | 20.8 m |
| 8 m | 4.3 m | 9.2 m | 16.0 m | 27.7 m |
| 10 m | 5.4 m | 11.5 m | 20.0 m | 34.6 m |
Recommended lux levels by application
These are typical design ranges for general guidance, not figures quoted from a standard. For commercial jobs, confirm targets against the relevant Australian standard, such as AS/NZS 1158.3.1 for outdoor car parks, AS/NZS 1680.5 for outdoor workplaces and the AS 2560 series for sports lighting.
| Application | Typical average lux |
|---|---|
| Security and perimeter | 5 to 20 |
| Driveway | 10 to 30 |
| Backyard and entertaining | 20 to 50 |
| Shed or workshop apron | 50 to 100 |
| Loading area | 50 to 150 |
| Car park | 10 to 30 |
| Tennis or basketball court | 200 to 350, depending on level of play |
How many lumens do you need by area?
Multiply area by target lux, then double the result. Doubling assumes about half the output is lost to spill, tilt and optics, which is a conservative allowance for outdoor floodlighting.
| Area | 10 lux | 30 lux | 100 lux |
|---|---|---|---|
| 25 m² | 500 lm | 1,500 lm | 5,000 lm |
| 50 m² | 1,000 lm | 3,000 lm | 10,000 lm |
| 100 m² | 2,000 lm | 6,000 lm | 20,000 lm |
| 200 m² | 4,000 lm | 12,000 lm | 40,000 lm |
| 400 m² | 8,000 lm | 24,000 lm | 80,000 lm |
Three worked Australian examples
- Driveway, 6 m x 12 m (72 m²) at 20 lux: about 2,900 lumens. Two fittings of roughly 1,500 lumens under the eaves at 3 metres, with wide beams, cover it more evenly than one.
- Backyard, 10 m x 8 m (80 m²) at 30 lux: about 4,800 lumens. Two 2,400 lumen fittings from opposite corners soften shadows around the table and barbecue.
- Shed yard, 15 m x 10 m (150 m²) at 75 lux: about 22,500 lumens. Three fittings of around 7,500 lumens at 5 to 6 metres on the shed wall, with 90 degree beams, suit this job.
Once you have a lumen figure, compare it against the specifications in the HEXA LED floodlights range. For light inside the building, see our shed lighting collection.
Choosing a beam angle: narrow, medium or wide
The higher the mounting point, the narrower the beam you generally need, because the cone has more distance to spread.
| Beam type | Angle | Typical mounting height | Best for |
|---|---|---|---|
| Narrow | 15 to 30 degrees | 8 m and above | Tall poles, long throws, signs and features |
| Medium | Around 60 degrees | 4 to 8 m | Shed yards, courts, loading areas |
| Wide | 90 to 120 degrees | 2.4 to 4 m | Driveways, patios, house walls |
Beam angle, field angle and optics
Light does not stop at the beam edge. The field angle is the wider cone measured down to 10 per cent of peak intensity, and light beyond the beam is spill. Symmetric optics throw a round cone. Asymmetric optics push light forward from a flat, downward facing lens, which lights a yard from its edge with less glare.
How far does an LED floodlight shine?
There is no honest single distance per wattage. Light never stops, it just gets weaker, so the real question is the distance at which it drops below a useful lux level. Illuminance on the beam axis equals candela divided by distance squared. A floodlight with a peak intensity of 10,000 candela gives about 10 lux at 32 metres and only 1 lux at 100 metres. Check the candela figure or photometric data, then decide what lux you need at the far end.
Tilt, spacing and neighbour glare
Tilting a floodlight stretches its round pool into a long ellipse. The near edge stays bright, the far edge fades, and more light escapes above the horizontal as glare. As a rule of thumb, aim the beam centre to land no further out than about twice the mounting height, and always keep the aim below horizontal. If you need more reach, mount higher.
For multiple fittings, space them roughly one beam spread apart so the 50 per cent edges overlap into an even level. Several mid power fittings usually beat one large one, with fewer shadows and less glare.
AS/NZS 4282 covers the control of the obtrusive effects of outdoor lighting, and many councils refer to it for light spill complaints and development conditions. Keep light inside your boundary, away from neighbours' windows and off the road. Check with your local council for commercial or sports lighting.
Australian compliance and IP ratings
- RCM mark: shows the supplier declares the product meets Australian electrical safety and EMC requirements.
- EESS: the Electrical Equipment Safety System, under which responsible suppliers and in-scope equipment are registered.
- AS/NZS 60598: the luminaire safety standard series, which includes specific requirements for floodlights.
- Installation: anything hardwired to 240V fixed wiring must be installed by a licensed electrician.
- IP rating: IP65 is dust tight and protected against water jets, and IP66 handles stronger jets. An IP rating does not cover salt corrosion, so check housing materials and fixings for coastal sites.
You can read more about our approach to compliant products on the Why HEXA page, and find related guides in the HEXA technical blog.
Step by step selection method
- Measure the area in square metres.
- Pick a target lux from the application table.
- Calculate lumens: area x lux x 2.
- Confirm your mounting height.
- Choose a beam angle using the beam spread table.
- Split the lumens across two or more fittings and plan the overlap.
- Check tilt, spill, IP rating and compliance markings.
Common floodlight mistakes
- Buying on watts instead of lumens.
- Using a wide beam on a tall pole, which wastes light as spill.
- Tilting the light towards the horizon to gain reach.
- Relying on one oversized fitting, which creates harsh shadows.
- Ignoring neighbours, council expectations and compliance markings.
Frequently asked questions
How many lumens do I need for an LED floodlight?
Multiply the area in square metres by your target lux, then double it to allow for spill and losses. A 50 square metre driveway at 30 lux needs roughly 3,000 lumens, while the same area lit as a work apron at 100 lux needs about 10,000 lumens.
What beam angle is best for a floodlight?
A wide beam of 90 to 120 degrees suits low mounting heights of 2.4 to 4 metres, where the light needs to spread quickly. Medium beams around 60 degrees suit 4 to 8 metres, and narrow beams around 30 degrees suit tall poles or long throws.
How far will an LED floodlight shine?
It depends on the lux level you count as useful. Illuminance falls with the square of distance, so a floodlight with a peak intensity of 10,000 candela delivers about 10 lux at 32 metres and only 1 lux at 100 metres.
Do I need an electrician to install an LED floodlight in Australia?
Any floodlight that is hardwired into 240V fixed wiring must be installed by a licensed electrician. Fittings supplied with a fitted plug can be used on a suitable weather protected socket outlet, following the manufacturer's instructions.
