Barn Lighting: LED for Livestock, Dairy Cows and Milking Parlours

In livestock buildings, light affects not only the work but also the animals: dairy cows give more milk with a well-controlled light programme, poultry is sensitive to flicker, and ammonia, dust and high-pressure cleaning demand particularly robust luminaires. This guide shows what light belongs in barns, milking parlours and ancillary rooms.

Lux levels on the farm

Area	Illuminance	Note
Cubicles, alleys for dairy cattle	approx. 150–200 lux (day)	Light programme approx. 16 h light, 8 h dark
Feed alley	approx. 200 lux	Encourages feed intake
Milking parlour	approx. 200–300 lux	Udder clearly visible, few shadows
Calving and sick pens	approx. 200–500 lux	Good colour rendering for diagnosis
Machinery shed, workshop	approx. 200–300 lux	See workshop lighting
Night light for checks	approx. 5–10 lux	Dimmed or red light

The values are guide values from standards and agricultural advisory services. For machinery sheds, see Vehicle Workshop Lighting.

Light programmes for dairy cows

Cows respond to day length. A long-day programme with about 16 hours of sufficiently bright light and 8 hours of real darkness can increase milk yield and improve feed intake. Dry cows, on the other hand, benefit from shorter days. This requires dimmable or switchable luminaire groups and a timer. During the dark phase, a weak night light is enough for checks.

Robust luminaires for livestock buildings

• Ammonia: Slurry and manure release ammonia, which makes ordinary plastics brittle. Ammonia-resistant luminaires last much longer.
• High-pressure cleaning: If you clean the barn with high pressure, you need IP69K (see IP Ratings Explained).
• Dust and insects: Closed, smooth housings without open cooling fins get less dirty.
• Flicker-free: Poultry and pigs perceive flicker at higher frequencies than humans. High-quality drivers with low ripple are therefore essential.

Luminaires for barns and agriculture

Yards and outdoor areas

Silage clamps, yards and runs are often used in the dark in winter. LED floodlights on buildings or poles bring light there, with motion sensors only when needed. How to plan outdoor areas is shown in Outdoor Lighting for Business Premises.

Worked example

Dairy barn with 30 fluorescent tri-proof fittings 2 × 58W (approx. 140W), 16 hours of light a day (5,840 h), €0.28/kWh. Replaced by 30 ammonia-resistant LED luminaires of 60W: saving 30 × 80W × 5,840 h = 14,016 kWh, around €3,900 a year, plus fewer failures from corrosion.

Frequently asked questions

How many lux do cows need in the barn?

For an effective long-day programme, around 150–200 lux at the animals' eye level for about 16 hours, followed by 8 hours of darkness.

Why ammonia-resistant barn luminaires?

Ammonia from slurry and manure degrades ordinary plastics and seals. Ammonia-resistant luminaires stay sealed and clear.

What protection rating do I need in a barn?

At least IP65; IP69K with high-pressure cleaning.

Does flickering light disturb animals?

Yes. Many animals perceive flicker at frequencies humans no longer see. Flicker-free drivers avoid stress.

Do I need a night light in the barn?

A weak night light of about 5–10 lux or red light allows checks without disturbing the day-night rhythm.

Cover photo: Adrian Michael, Wikimedia Commons, licence CC BY-SA 2.5.