When it comes to bright outdoor lighting, the key factor to consider is the number of lumens the light bulb or fixture provides. Lumens measure the total amount of visible light a light source emits. The more lumens, the brighter the light.
What is a lumen?
A lumen is a measure of the total amount of visible light emitted by a light source. It indicates the brightness or intensity of the light. More lumens means a brighter light. For example, a 100-watt incandescent light bulb produces about 1600 lumens.
How many lumens for outdoor lighting?
The number of lumens needed for outdoor lighting depends on the size of the area you want to illuminate. As a general guideline:
- For a small confined outdoor area like an entryway or patio, look for a light bulb or fixture that provides 1000-2000 lumens.
- For a medium-sized area like a driveway or garden path, look for 2000-4000 lumens.
- For a large open yard or exterior entertaining area, you’ll need 4000-6000 lumens for bright illumination.
Here are some specific lumen recommendations for common outdoor spaces:
| Outdoor Area | Recommended Lumens |
|---|---|
| Small entryway | 1000-2000 |
| Front porch | 2000-3000 |
| Back patio/deck | 3000-5000 |
| Driveway | 3000-4000 |
| Small yard | 4000-6000 |
| Large yard | 6000-8000 |
Factors that affect lighting needs
In addition to the size of the space, other factors that influence your outdoor lighting needs include:
- Intended use: If you plan to use the space for tasks like grilling or gardening, you’ll need brighter light than just basic security and visibility.
- Surrounding conditions: Bright competing lights from neighboring homes, streets and businesses increase the amount of light needed.
- Reflective surfaces: Areas with light-colored walls, pavements and vegetation reflect light better, so you may need fewer lumens.
- Amount of vegetation: Trees, shrubs and other plants can block light, so densely landscaped yards need more lumens.
- Nighttime use: The later you use a space at night, the more light you’ll need to overcome darkness.
Also consider the age of those using the space. As we get older, we need brighter light to see well. Boosting lumens in outdoor areas used by seniors makes them safer and more accessible.
Lumens for security lights
Outdoor security lighting has the specific purpose of deterring intruders, enhancing safety and providing better visibility at night. Here are some common lumen amounts for security lights:
- 500-900 lumens: Good for accent lighting, illuminating a small entryway or highlighting architectural features.
- 900-1800 lumens: Appropriate for porch lights, spotlights or small security cameras.
- 1800-3000 lumens: This brightness works well for driveway or wide area security lights.
- 3000+ lumens: Very bright security floodlights for large open areas and corners of buildings.
Keep in mind that many security lights use motion sensors or timers to temporarily provide extra bright lighting when needed, then revert to a lower lumen level. So the labeled lumens may indicate peak brightness, while average use is lower.
Lumens for spotlights and floodlights
Spotlights and floodlights concentrate light in a focused beam for accenting architectural features, landscape elements or other exterior details. Here are typical lumen amounts:
- 500-1000 lumens: Good for spotlighting small statues, planting beds or lighting steps.
- 1000-2000 lumens: Appropriate for lighting up garage doors, patios or signs.
- 2000-4000 lumens: This brightness range works well to accent trees, fountains or corners of buildings.
- 4000+ lumens: Ultra-bright spotlights and floodlights for large outdoor areas.
The more focused and directional a light is, the higher the lumen amount needed to provide sufficient brightness. Floodlights spread light over a wider area so they require fewer lumens than a comparable spotlight.
Lumens needed by light bulb type
Certain types of light bulbs produce more lumens than others. Here are typical lumen outputs for common bulb varieties used in outdoor lighting:
- Incandescent: 600-2600 lumens
- Halogen: 1000-3000 lumens
- CFL: 450-1600 lumens
- LED: 450-8000 lumens
- High intensity discharge: 2000-20000 lumens
- Mercury vapor: 2500-6000 lumens
- Metal halide: 5000-20000 lumens
- High pressure sodium: 8000-50000 lumens
So if you know you need a minimum of 2000 lumens for your patio, an LED or halogen bulb may be a good option. For lighting a large parking lot that requires 30000 lumens, a high intensity discharge or high pressure sodium light would provide those high lumen levels.
Light color temperature
In addition to brightness, you also need to consider light color or temperature for outdoor spaces. This is indicated in units called Kelvin (K). The most common ranges are:
- Warm white: 2700K-3000K. Gives off an amber, cozy glow great for accent lighting.
- Soft white: 3000K-4000K. A comfortable everyday color for porches, walkways, etc.
- Bright white: 4000K-5000K. Crisp cool color, similar to daylight.
- Daylight: 5000K-6500K. Bright bluish-white light. Best for task lighting.
Choosing light color depends on personal preference and the impression you want to create. Warmer color temperatures like 2700K to 3000K work well for creating an inviting ambiance in outdoor living areas. Cooler colors in the 4000K to 6000K range are good for illuminating tasks and security lighting.
Putting lumens and Kelvin together
When shopping for outdoor lighting, look at both lumens and Kelvin together to find lights that provide the ideal brightness and light color. Here are some pairings that work well together:
- Porch lights: 2500-3000 lumens, 3000K
- Entryway lights: 1500-2000 lumens, 3000K-4000K
- Driveway lights: 4000-6000 lumens, 4000K-5000K
- Security floodlights: 5000+ lumens, 4000K-5000K
- Accent uplighting: 500-1000 lumens, 2700K
Combining the lumens you need for adequate brightness with a light color suitable creates great outdoor illumination.
Lumens and bulb life
One downside of high lumen bulbs is they consume more energy and burn out faster than lower lumen bulbs. Here are some comparisons of relative bulb life:
| Bulb Type | Lifespan Range |
|---|---|
| 600 lumen incandescent | 750-1000 hours |
| 1600 lumen incandescent | 500-750 hours |
| 800 lumen CFL | 6000-15000 hours |
| 1600 lumen CFL | 3000-6000 hours |
| 800 lumen LED | 25000-50000 hours |
| 1600 lumen LED | 15000-30000 hours |
So while a 1600 lumen incandescent yields bright light, it lasts for less than a year with average use. An equally bright 1600 lumen LED can provide up to 30 years of life. This makes LEDs the best option for long-lasting outdoor illumination.
Dimmable vs non-dimmable bulbs
Many outdoor lighting fixtures offer dimming capability. This allows you to lower light levels when full brightness isn’t needed. Dimmable bulbs have a couple advantages:
- They last longer since reducing brightness extends lifespan.
- You can set mood lighting at lower illumination.
- Dimming saves energy when less light is required.
However, dimmable bulbs cost a bit more than non-dimmable. Also, the stated lumens on dimmable bulb packaging indicates maximum brightness. At 50% dimming the light output is roughly halved.
So if you install a 4000 lumen dimmable bulb but run it at 50% brightness, you’re only getting around 2000 lumens. Make sure to factor dimming settings into your lumen requirements when designing lighting.
Lumens and bulb shape
Outdoor lighting bulbs come in a variety of shapes like traditional A-shape, torpedo, bullet, PAR, R-lamp, MR16, and more. Some produce light in all directions. Others, like PAR and MR16 bulbs, concentrate light in a narrow directed beam. Here are lumen comparisons for common bulb shapes:
| Bulb Shape | Typical Lumens Range |
|---|---|
| A-Shape Standard Bulb | 400-2600 |
| BR Shape Bulb | 300-1000 |
| PAR Bulb | 250-5000 |
| R Lamp Bulb | 1400-2200 |
| MR16 Bulb | 250-1000 |
Reflector (R) and parabolic aluminized reflector (PAR) bulbs don’t require as many lumens to achieve the same perceived brightness as general service (A-shape) bulbs. So you may be able to use fewer lumens with spotlights or recessed directional lighting.
Lumens needed by fixture
Outdoor lighting fixtures also have an overall lumen rating. This indicates the total light output you can expect from that fixture based on the bulb used. Fixture lumens help match the fixture to the lighting needs of the space. Here are some common fixture lumen amounts:
- 100-400 lumens: Wall sconces, LED step lights
- 400-1000 lumens: Low-voltage pathway lighting, stair rail lights
- 1000-2000 lumens: Entryway chandeliers, small porch sconces
- 2000-4000 lumens: Large porch lighting, wall lanterns
- 5000+ lumens: Barn lights, large area flood lights
Again, these are total lumens for the entire fixture, not just for the bulb. A porch light rated at 2400 lumens outfitted with a 2000 lumen bulb will give you 2000 lumens of illumination.
Placing outdoor lights
Proper placement enhances your outdoor lighting plan. Position fixtures to avoid glare and shadows:
- Use ample, evenly placed lights along paths and stairs. Putting light at the top and bottom of stairs is safer.
- Place lights above eye level to reduce glare. If light shines into your eyes, brighten the area below it instead.
- Lights on either side of the front door create even illumination for safer entry and exit.
- Position floodlights higher up aiming down to wash exterior walls with light.
- Use uplighting directed up at structures to highlight architectural details.
Take into account overlapping light patterns when locating multiple fixtures. Space them accordingly to achieve consistent brightness over the entire area.
Calculating lumens needed
If planning complex outdoor lighting requiring exact lumen calculations, you can use this basic formula:
Total Lumens Needed = (Square Footage x Desired Footcandles) / Efficacy
Where:
- Square Footage is the size of the area to be lit.
- Desired Footcandles indicates the target light intensity. 10-20 footcandles is common for exterior lighting.
- Efficacy is the fixture efficiency rating, typically found on packaging or in product specs. LEDs have efficacy ratings around 100. For other bulbs it’s normally 10-20.
For example, to light a 400 square foot patio to 15 footcandles using an LED fixture rated at 100 efficacy:
Total Lumens = (400 x 15) / 100 = 6000 Lumens
So you’d need around 6000 lumens to properly illuminate that patio space. Using this quick calculation, you can determine the precise lumen needs for any outdoor area.
Conclusion
Outdoor lighting can seem complicated because of all the different lumen amounts, beam spreads, color temperatures and bulb types. But focus first on the size of the area you want to illuminate and how you plan to use the space at night. From there you can narrow down the appropriate number of lumens and other factors that meet your lighting goals.
Stick to the lumen ranges outlined here for typical exterior spaces. Also look at fixture lumens when selecting lights to handle the desired brightness. And remember, more lumens provide extra brightness but consume more energy. So only use what you need for a space to balance light quality and efficiency.
