If you're retrofitting a warehouse or specifying fixtures for a new office, the choice between LED and T5 fluorescent comes down to three things: total cost of ownership, light quality, and how long you plan to stay in the building. LED wins on lifespan and energy efficiency — we're talking 50,000 hours vs 20,000 hours typical for T5 — but T5 still holds its own on upfront cost and color rendering in certain applications. Here's the thing: the gap has narrowed dramatically since 2020. Let's break it down with real numbers.
Head-to-Head Comparison
Parameter
LED
Fluorescent T5
Winner
System Efficacy (lm/W)
120–140 lm/W at 4000K, typical for commercial panels
90–105 lm/W for standard T5HO, per IEC 60081
LED
Rated Lifespan (L70)
50,000–60,000 hours (LM-80 tested)
20,000–30,000 hours (per IEC 60081)
LED
Color Rendering Index (CRI)
80–90 typical; 95+ available for premium
80–85 standard; 90+ with triphosphor tubes
Tie (LED edges ahead at high CRI)
Correlated Color Temperature (CCT)
2700K–6500K, tunable options available
3000K–6500K, fixed per tube
LED
Upfront Cost (per fixture)
$30–$80 for a 4-foot, 40W equivalent
$15–$35 for fixture + tube
T5
Energy Cost (annual, 10 hrs/day)
$18–$25 per fixture at $0.12/kWh
$28–$38 per fixture at same rate
LED
Maintenance (relamping interval)
Every 7–10 years
Every 2–3 years
LED
Dimming Capability
0–100% with standard 0-10V or DALI
Limited; requires special ballasts, 10–100% typical
LED
Environmental (mercury content)
None; RoHS compliant
3–5 mg per tube (EU RoHS exemption)
LED
Warranty
5–10 years typical
1–3 years for ballast; tube warranty varies
LED
Cold Start Performance
Instant on, even at -40°C
Delayed start below 0°C; flicker common
LED
Flicker (at 120 Hz)
Typically <5% with quality drivers
20–30% with magnetic ballasts; <5% with HF electronic
LED
Detailed Analysis
1. Performance
Let's put numbers to this. A standard 54W T5HO tube running on an electronic ballast delivers about 4,800 lumens — that's 89 lm/W system efficacy, per IEC 60081. A comparable LED linear tube at 40W pushes 5,200 lumens, hitting 130 lm/W. That's a 46% efficiency gain. What does this mean in practice? In a 10,000 sq ft warehouse running 200 fixtures 16 hours a day, you're looking at roughly $4,200 in annual energy savings with LED.
Lifespan is where the gap really opens up. LED tubes rated per LM-80 and TM-21 typically hit 50,000 hours to L70 — that's 70% of initial lumens maintained. T5 tubes, even with good ballasts, rarely exceed 30,000 hours before you're swapping them out. I've been on job sites where T5s in a 24/7 cold storage facility needed relamping every 18 months. LED in the same application? Five years and still going strong.
2. Cost Analysis
Here's the honest truth: T5 still wins on sticker price. A basic 4-foot T5 fixture with tube runs you $15–$25. An equivalent LED fixture is $30–$80. That's 2–3x more upfront. But — and this is the catch — the payback period on that premium is usually 12–18 months in energy savings alone, assuming $0.12/kWh and 10-hour operation. Factor in maintenance labor (which runs $50–$100 per relamp in commercial settings), and LED breaks even even faster.
Bottom line: if you're building for a 5-year lease, T5 might make sense on paper. If you own the building or plan to be there 10+ years, LED is the only rational choice. I've seen facilities that went T5 to save $5,000 upfront and ended up spending $18,000 on relamping over the next 6 years. Don't be that buyer.
3. Application Suitability
T5 still has a place — mostly in retrofit situations where you're keeping existing fixtures and just swapping tubes. It's also decent in applications where you need very high CRI (95+) on a budget, though premium LED now matches that. For new construction, LED is the default. For cold environments (freezers, parking garages), LED's instant-on at -40°C is a killer feature. For spaces with frequent dimming or occupancy sensors, LED's 0–100% range beats T5's clunky 10–100% every time.
4. Pros & Cons
LED Pros: 50,000+ hour lifespan, 120–140 lm/W efficacy, no mercury, instant start, 0–100% dimming, 5–10 year warranty. Cons: Higher upfront cost, potential compatibility issues with existing T5 ballasts (if retrofitting), heat sensitivity in enclosed fixtures.
50,000 hr lifespan, 130 lm/W, 0–10V dimming standard
Warehouse retrofit (existing T5 fixtures)
LED (direct wire or plug-and-play)
Energy savings of 30–40%, no ballast maintenance
Cold storage / freezer (-20°C)
LED
Instant start at -40°C; T5 fails below 0°C
Budget-constrained rental space (5-year lease)
T5
Lower upfront; no long-term ownership benefit
High-CRI retail display (95+ CRI)
LED (premium)
LED now matches T5 at 95+ CRI with better efficiency
Parking garage with occupancy sensors
LED
Instant on/off, 0–100% dimming, no warm-up delay
Final Recommendation
Verdict: LED is the clear winner for 90% of commercial and industrial applications. The only scenario where T5 still makes sense is a short-term rental (under 5 years) where you're minimizing upfront capital and don't care about energy costs. For everything else — new construction, retrofits, cold environments, or any space with controls — LED delivers lower total cost of ownership, better light quality, and zero mercury liability. If you're specifying today, go LED. Your maintenance team will thank you in year 4 when they're not changing tubes.