LED Panel Lights: A Buyer's Guide for Office, Retail, and Commercial Installations

LED Panel Lights: A Buyer's Guide for Office, Retail, and Commercial Installations

LED panel lights have become the standard ceiling light fitting for offices, retail premises, commercial kitchens, schools, and healthcare facilities across the UK. They replace traditional fluorescent tube fittings (T8 and T5 fluorescents) with a flat, even-output LED panel that produces less glare, uses significantly less energy, and requires no lamp replacement for the rated lifespan of the fitting. This guide covers panel types, specifications, sizing, and correct selection for common commercial and light-industrial applications.

Why LED Panels Have Replaced Fluorescent

Traditional grid ceiling installations used 600mm × 600mm recessed fluorescent fittings with T8 or T5 tubes. These fittings had several limitations: tubes required periodic replacement, the starting gear (magnetic or electronic ballast) added cost and generated heat, and the linear tube layout created uneven light distribution with bright lines visible through the diffuser.

LED panels address all these issues:

• Lifespan: Good-quality LED panels carry L70 ratings of 50,000 hours or more — meaning output does not fall below 70% of initial lumens until 50,000 hours of use. At 12 hours per day commercial use, this is over 11 years with no lamp replacement.
• Efficiency: Modern LED panels achieve 100–130 lumens per Watt. A 40W LED panel replacing a 2× 36W T8 fitting (72W plus ballast losses) reduces energy consumption by 45–50%.
• Even distribution: The edge-lit or direct-lit LED panel produces diffuse, even output with no visible hot spots — better comfort and lower UGR (Unified Glare Rating) for screen-based workplaces.
• No maintenance lamp cost: The fitting and LED module are replaced as a unit at end of life, eliminating ongoing lamp and maintenance costs.

Panel Sizes

LED panel sizes correspond to standard suspended ceiling grid dimensions:

• 600mm × 600mm: The dominant size for UK commercial ceiling grids. Designed to drop into a standard 600 × 600 suspended ceiling tile grid. Available in recessed (lay-in) and surface-mount versions. Output typically 30–48W, replacing a 2× 36W T8 recessed fitting.
• 1200mm × 300mm: Linear panel for 1200 × 300mm grid ceilings, or for surface mounting on flat ceilings without a grid. Growing in popularity for contemporary offices and retail environments where a linear rather than square appearance is preferred.
• 1200mm × 600mm: High-output panel for spaces requiring more lumens per fitting — warehouses, production areas, large open-plan offices. Typically 60–80W output.
• 600mm × 300mm (1/2 panel): Used in narrower grid bays, corridors, and spaces where the full 600 × 600 would overhang structure.
• Circular panels: 200mm–400mm diameter circular LED panels for domestic and hospitality applications — bathrooms, kitchens, reception areas. Not part of the suspended grid system; surface or flush-recessed mount.

Edge-Lit vs Direct-Lit (Back-Lit)

Two internal constructions are used in LED panels:

• Edge-lit: LEDs are arranged around the perimeter of the panel and the light is directed inward through a light guide plate (LGP), then diffused through the face panel. Produces a very slim profile (typically 10–15mm deep) — the profile that most people associate with the modern LED panel look. Uniformity across the face can vary in lower-quality panels — look for uniformity ratios of 0.7 or higher. Edge-lit panels are suitable for all standard commercial applications.
• Direct-lit (back-lit): LEDs are mounted on the rear of the panel directed toward the face, with a diffuser sheet. Slightly thicker (20–40mm), but generally produces better uniformity and higher lumen output per Watt. Preferred for higher-output applications and where uniformity specification is critical (healthcare, detailed workplaces).

For most standard office and retail installations, edge-lit panels are adequate and cost-effective. For detailed task environments or healthcare areas, specify direct-lit for better uniformity.

Wattage and Lumen Output

Do not specify panels by wattage alone — specify by lumen output. The lumen output determines the actual light level in the space; the wattage merely tells you the running cost. Common outputs for 600 × 600mm panels:

• 24W: approximately 2,000–2,400 lm — suitable for lower-demand areas, corridors, store rooms
• 36W: approximately 3,200–3,800 lm — standard office and retail output
• 40W: approximately 3,600–4,200 lm — higher-demand offices, classrooms
• 48W: approximately 4,400–5,000 lm — high-output requirements, areas with high ceilings or demanding lux targets

For office environments, the CIBSE Lighting Guide (LG7) recommends an average maintained illuminance of 500 lux at desk level. For a 3m × 3m office bay with a 2.7m ceiling height, one 36–40W panel (3,600–4,200 lm) typically achieves 400–500 lux — use a lighting design tool or confirm with the manufacturer's photometric data for the actual installation geometry.

Colour Temperature

LED panels are available in several correlated colour temperatures (CCT):

• 3000K (Warm White): Amber-warm tone, similar to incandescent. Suitable for hospitality, retail environments selling warm-coloured merchandise (bread, clothing), and healthcare areas where a relaxing atmosphere is required.
• 4000K (Cool White / Natural White): Neutral white — the standard specification for offices, schools, and most commercial environments in the UK. Supports alertness and colour perception without the harsh blue cast of 6500K.
• 6500K (Daylight): Blue-white tone. Used in technical workplaces requiring colour-accurate assessment (print rooms, clinical areas, quality inspection), and in some retail environments to create a bright, modern appearance. Not suitable as general office lighting for long-duration tasks — the high blue content can cause eye fatigue.

For most UK office and commercial fit-outs, specify 4000K. Some architects specify 3000K for reception and client-facing areas for a warmer, more welcoming appearance.

Colour Rendering Index (CRI)

CRI measures how accurately a light source renders colours compared to natural daylight (CRI 100). For most commercial applications, CRI 80+ is adequate. For retail (where product colour matters for purchase decisions), food preparation areas, and healthcare environments, specify CRI 90+. Low CRI panels (CRI 70 or below) make colours appear flat and muted — avoid for customer-facing areas.

Emergency Versions

Many LED panels are available in maintained or non-maintained emergency versions, or as standard panels with an emergency pack fitted as a separate module inside the fitting. Requirements under BS 5266:

• Emergency lighting must provide a minimum of 3 hours of operation on mains failure
• In escape routes, the maintained illuminance level must be at least 1 lux along the centreline
• Emergency fittings must be tested periodically — monthly function test, annual full 3-hour discharge test
• Emergency LED panels with self-test capability (automatic regular test with pass/fail indicator) simplify maintenance compliance significantly in large installations

Always confirm with the responsible person (building manager, fire officer) whether emergency LED panels are required in a particular installation before specifying standard panels throughout.

DALI and Dimming

Many LED panels are available with DALI (Digital Addressable Lighting Interface) control or 0–10V dimming:

• DALI: Two-wire digital control bus allowing individual addressing of each fitting from a DALI controller or building management system. Each fitting can be set to a different level, grouped with other fittings, or programmed for time/occupancy/daylight-linked control. Standard for modern office and commercial buildings with a BMS.
• 0–10V dimming: Analogue control signal on a separate wire pair — simpler to install than DALI, suitable for zone-based dimming without individual addressing. Common in smaller commercial and light industrial installations.
• TRIAC/phase-cut dimming: Standard dimmer switch compatible. Available on some LED panels but less common for commercial applications — more relevant for domestic panel fittings.
• Non-dimmable: Fixed output — the most common and lowest-cost option for basic commercial installations without a lighting control system.

IP Rating and Special Environments

Standard LED panels are rated IP40 or IP44 — suitable for dry indoor environments. For installations in food preparation areas, washrooms, and areas subject to cleaning with water spray, specify:

• IP54 or IP65 for areas subject to water splashing
• IP65 or IP66 for direct water jet cleaning (commercial kitchens, food processing)
• Antimicrobial coated panels or sealed panels for healthcare areas where surface hygiene is critical

Standard office-grade panels must not be installed in wet areas. Check the IP rating against the environment before specifying.

Installation Types

• Recessed (lay-in): Drops into the suspended ceiling grid — the standard commercial installation. The panel rests on the grid frame. Wire connection into a junction box above the grid.
• Surface mount: Fixed directly to a flat ceiling with a surface-mount frame or back box. Used where there is no suspended grid, or in areas where a recessed installation would compromise the structure above (concrete ceilings, timber joists without sufficient void).
• Suspended (pendant): Hung from the ceiling on suspension cables or rods — used in warehouses, production areas, and contemporary open-plan offices with exposed structural ceilings. Requires suspension kits as an additional accessory.

LED Panels at APM Plumbing & Electrical

APM stocks a range of LED panel lights for commercial installation — 600 × 600mm recessed panels in 36W and 40W, 1200 × 300mm linear panels, and emergency-pack versions. Both 4000K and 3000K colour temperatures available. All panels in the APM range are UKCA/CE marked and tested to BS EN 60598.

Browse our LED panel lights or contact the Acton trade counter for project quantities. Trade orders placed before 2pm ship same day.

Products Available from APM Plumbing & Electrical

Key LED panel lights available for trade collection or delivery:

Get It from APM Electricals

APM Electricals, 24 Western Avenue, Acton, London W3 7TZ. Call 020 8702 8080 or visit www.apmi.uk for same-day trade counter collection and next-day delivery across London and the UK.