Recommended Lux Levels for Car Dealership Lighting

Recommended Values by Application

Specification Comparison

Why Lux Matters

Let's put numbers to this. A car's paint finish reflects between 4% (matte) and 90% (gloss clear coat) of incident light. At 750 lux horizontal on a glossy sedan hood, you're getting roughly 675 lux reflected into the customer's eye. Drop that to 300 lux, and you're at 270 lux reflected — the difference between "wow" and "meh."

Here's the thing: vertical illuminance on the vehicle sides is what sells the car. IES RP-29-16 specifically calls out 500 lux vertical at 1.5m height — that's the beltline of most sedans and SUVs. I've been on site where a dealer installed 1000 lux horizontal but only 150 lux vertical. The floor was blinding, but the cars looked flat. You need both.

Color temperature matters too. For showrooms, 4000K to 5000K is standard per CIE S 008:2001. Below 3500K, metallic flakes look muddy. Above 6000K, interiors look cold and clinical. I've seen dealers try 6500K and customers complained the leather looked "washed out." Stick to 4000K for general, 5000K for accent on paint.

What about glare? EN 12464-1 caps UGR at 19 for showrooms. That's not arbitrary — a UGR of 22 causes visible discomfort in 50% of observers per CIE 117:1995. In a dealership, you're asking customers to stare at shiny surfaces for 20+ minutes. Keep UGR ≤19, ideally ≤16 with indirect/direct luminaires.

Application Scenarios

Scenario 1: Premium Showroom (500 m², 8m ceiling)
You need 750 lux horizontal at 0.75m workplane height. With a 4m mounting height and 60% ceiling reflectance, a 1200mm linear LED at 4000K, 90 CRI, delivering 3500 lm per fixture, spaced 2.5m x 2.5m, gets you there. Add track heads at 3000 lm each on 1.5m centers aimed at vehicle sides for vertical fill. Total load: ~18 W/m². That's per EN 12464-1 Table 5.1 and verified by Dialux simulation.

Scenario 2: Service Bay (200 m², 5m ceiling)
General 300 lux horizontal per EN 12464-1 Table 5.26. Use IP65-rated linear fixtures at 4000K, 80 CRI, 130 lm/W, mounted at 4m. Spacing 3m x 3m. For inspection pits, add portable LED work lights at 2000 lm each, 5000K, with magnetic bases. I've seen too many service bays where the under-vehicle area gets 50 lux — that's a safety hazard and a warranty claim waiting to happen.

Scenario 3: Exterior Lot (2000 m²)
Average 50 lux per CIE S 008:2001. Use 15m poles with 150W LED floodlights at 5000K, 130 lm/W, 60° beam. Spacing 20m x 20m gives 55 lux average with 3:1 uniformity. Add bollard lights at 10m intervals along pedestrian paths at 20 lux minimum per EN 12464-2:2014. Don't forget — the lot needs to look inviting at night, not like a prison yard.

Scenario 4: Parts Storage (100 m², 4m ceiling)
Aisles at 200 lux horizontal, bin faces at 300 lux vertical. Use 1200mm linear LEDs at 4000K, 80 CRI, mounted parallel to aisles at 3m height. Spacing 2.5m x 3m. Add a 10° asymmetric lens on the row closest to bins to throw light onto vertical labels. This follows IES RP-29-16 Section 7.1 — and trust me, your parts guys will thank you when they can read part numbers without a flashlight.

Design Guidelines

Start with the vehicle as the target. Measure vertical illuminance at 1.5m height on both sides — that's where the paint and trim live. Horizontal lux on the floor is secondary.

Use a mix of direct/indirect luminaires. Direct light gives the 750 lux punch; indirect light at 200–300 lux fills shadows and keeps UGR down. I've seen dealers try all-direct and customers squint. All-indirect and the cars look dull. Balance is everything.

For LED selection, target 130–150 lm/W at 4000K for linear panels, 120–140 lm/W for track heads. L70 at 50,000h minimum per IES LM-80-15. Don't cheap out on drivers — IEC 62384 compliant with 0–10V dimming for showroom zones. You'll want to dim to 10% for evening events.

Calculate using the lumen method: N = (E × A) / (Φ × UF × MF). For a 500 m² showroom at 750 lux, with 3500 lm fixtures, UF 0.65, MF 0.8, you need N = (750 × 500) / (3500 × 0.65 × 0.8) = 206 fixtures. That's a lot. But it's what the standard says. I've done this calc on site and it holds up.

Bottom line: always commission a Dialux or Relux simulation before buying. The difference between a calculated 750 lux and an actual 680 lux is often just a 0.1 lower room reflectance than you assumed. Measure after install.

Key Takeaways