Lighting is the single most-touched, least-specified system in most office fit-outs. Teams will argue for weeks about chair fabric and acoustic baffles, then accept whatever 600x600 panel the contractor has in stock at 4000K across the whole floor plate. The result is a space that photographs fine and feels wrong: flat, glary on screens, harsh in focus rooms and dim where people actually read. Good office lighting design is not about lumens-per-square-foot as a single number. It is about putting the right light, at the right intensity and colour, in the right place, with controls that let the space change through the day.
This guide covers what we actually specify when we design lighting for offices in Mumbai and Pune: target lux levels by zone, colour temperature and human centric lighting, controlling glare, integrating daylight, energy and controls strategy, and the often-forgotten requirement of lighting people for video. Treat it as a checklist you can hold your fit-out partner and MEP consultant to.
Lux levels by zone: stop lighting the whole floor the same
The most common mistake is a single uniform illuminance target applied everywhere. Different activities need different light. The relevant reference for India is the National Building Code along with IS 3646 and the international baseline of EN 12464-1, which set maintained illuminance on the working plane (typically 0.75m above floor) rather than at the ceiling. "Maintained" matters: it is the level you must still meet at the end of the maintenance cycle, after lumen depreciation and dirt, so you design the new installation roughly 20–30% above it.
Use the table below as a starting specification, then tune to the actual tasks. Note that open workstations in a paperless office can sit at the lower end because the visual task is a self-illuminated screen, not paper.
| Zone | Maintained lux (working plane) | Colour temperature (CCT) | Notes |
|---|---|---|---|
| Open-plan workstations | 300–500 lux | 3500–4000K | Lower end if screen-based; add task lights for paper work |
| Focus / meeting rooms | 300–500 lux | 3500–4000K | Dimmable; vertical light on faces matters for video |
| Reception / lounge | 150–300 lux | 2700–3000K | Warm, layered, accent-driven; not a workstation level |
| Cafeteria / breakout | 200–300 lux | 3000K | Warmer to signal "off-task" recovery space |
| Corridors / circulation | 100–150 lux | 3000–4000K | Keep below adjacent rooms to avoid a tunnel effect |
| Drawing / lab / fine detail | 500–750 lux | 4000K | High illuminance plus high colour rendering |
| Server / utility | 200 lux | 4000K | Functional only |
Two numbers belong next to every lux target in the lighting BOQ: uniformity (U0, ideally 0.6 over the task area so you do not get pools and shadows) and colour rendering (CRI/Ra 80 minimum for general areas, 90+ where colour judgement, branding, or video matter).
Colour temperature and human-centric lighting
Colour temperature, measured in Kelvin, sets the mood and the alertness of a space. Lower CCT (2700–3000K) reads warm and relaxing; higher CCT (4000K and above) reads crisp and alert. The lazy default is 4000K everywhere, which makes a cafeteria feel like a clinic. Match CCT to function: warm in hospitality and recovery zones, neutral-to-cool at the desk.
Human centric lighting (HCL, also called circadian lighting) goes a step further. The human body clock responds strongly to bright, blue-rich light in the morning and dimmer, warmer light in the evening. Tunable-white luminaires shift both intensity and CCT across the day. Say 5000K and high output mid-morning, drifting to 3000K by late afternoon. To support alertness when it is needed and wind-down later. It is worth the premium in always-on environments: GCC delivery floors running shifts, control rooms, and clinical spaces. For a standard 9-to-6 office, a well-designed daylight-and-warm-evening scene captures most of the benefit at a fraction of the cost. Decide this early, because tunable-white drivers, wiring, and control gateways have to be designed in, not retrofitted; our MEP engineering team coordinates the driver and DALI topology so the control intent survives into the as-built.
Glare control: the difference between bright and comfortable
Glare is what people mean when they say a space is "too bright" even at correct lux. There are two kinds, and both have to be designed out. Direct glare is light from the luminaire hitting the eye; it is quantified by the Unified Glare Rating (UGR), and for screen-intensive offices you want luminaires rated UGR < 19. Reflected glare is luminaires or windows mirrored in monitors and glossy surfaces. The veil that washes out a screen.
- Specify low-UGR luminaires with proper optics. Micro-prismatic diffusers, louvres, or deep-set/honeycomb optics. Not bare LED panels with exposed diodes.
- Orient linear fittings and desks so screens sit side-on to luminaire rows and to windows, never with a window directly behind or in front of the user.
- Use indirect or direct/indirect fittings (uplight bouncing off the ceiling) to lift perceived brightness without a hard source in the field of view.
- Treat windows as glare sources too: solar-control glazing or internal blinds belong in the lighting conversation, not just the facade one.
Glare control is where lighting and interiors have to move together. Ceiling finish, partition placement, desk orientation, and material gloss all change the outcome, so we run this in parallel with the interior design and 3D stage and validate it in renders before anything is ordered.
Daylight integration and zoning
Daylight is free, high-quality, and good for wellbeing. But only if it is managed. The goal is to harvest it, not just have a glass box that overheats and glares. Three moves matter. First, lay out the floor so daylight reaches deep: open zones near the glass, enclosed rooms and stores pushed inboard, glazed partitions so light penetrates rather than getting trapped at the perimeter. Second, install daylight-linked dimming on the perimeter rows so artificial light backs off automatically when the sun is doing the work. Typically the fastest-paying control upgrade on the floor. Third, control solar gain and glare with the facade and blinds so people near the windows are not forced to shut everything out by 11am, which defeats the purpose.
This is also a green-building lever. Daylight access, glare control, and lighting controls all carry credits under IGBC, LEED, and WELL, so if a certification target is in play, the lighting and daylighting strategy should be set against those criteria from the test-fit stage, not patched in before the audit.
Energy efficiency, controls and standards
Lighting is one of the larger electrical loads on a fit-out, and it is also where the easiest energy savings live. Through controls, not just efficient lamps. LED is a given now; the differentiators are the control layer and the maintained design margin. A sensible controls stack for an office floor:
- Occupancy / vacancy sensing in meeting rooms, focus rooms, toilets, and store areas. Absence detection that switches off after a set delay beats relying on people.
- Daylight harvesting on perimeter and atrium-adjacent zones as above.
- Zoning and scenes via DALI or a comparable addressable system, so areas are controlled in small groups and meeting rooms get presentation/video scenes rather than all-on or all-off.
- Time scheduling for cleaning, after-hours, and base-build hours, with manual override at the zone.
Specify Luminaire Efficacy in lumens per watt and a target Lighting Power Density (W/m²) in the brief. It forces the design to be efficient rather than just bright, and it is the number ECBC and most green ratings care about. Emergency and egress lighting, exit signage, and the fire NOC requirements are non-negotiable and must be designed in by the MEP consultant from the outset, not value-engineered out late. Keep emergency luminaires and the maintained-illuminance calculation in the same lighting layout so nothing is double-counted or missed at snagging.
Lighting for video calls and AV rooms
Since hybrid work became permanent, every meeting room is a broadcast studio, and ceiling-only lighting fails on camera. Overhead light alone leaves eye sockets in shadow and lights the top of the head. The fix is vertical illuminance on faces: front-of-room light, soft and even, at the seated face height. Wall-wash, a lit front wall, or dedicated fittings angled toward the table, not just downlights over it. Keep one colour temperature across the room (mixed 3000K and 5000K on skin looks awful on camera), aim for CRI 90+ so skin tones read true, and make the room dimmable so a bright presentation scene and a softer video scene are both available. For premium boardrooms and town-hall spaces, the lighting, AV, and acoustic design should be coordinated as one package so a pendant does not end up hanging through the camera's sightline.
Frequently asked questions
For screen-based open-plan work, design for a maintained 300–500 lux on the desk (the working plane), not at the ceiling. Screen-only tasks can sit toward 300 lux with task lights available; anyone doing paper or detailed work wants the upper end or a dedicated task light. Always pair the lux target with a uniformity figure (U0 ~0.6) and CRI 80+ so the level is even and colours read true.
It depends on how the floor is used. For always-on environments. Shift-based GCC delivery teams, control rooms, clinical or low-daylight spaces. Tunable-white HCL genuinely supports alertness and is worth specifying. For a standard daytime office with good daylight, a simpler strategy of daylight harvesting plus a warm evening scene captures most of the benefit far more cheaply. Either way, decide before first fix, because tunable-white wiring and DALI control have to be designed in, not retrofitted.
Specify low-glare luminaires rated UGR below 19 with proper optics rather than bare LED panels, orient desks and linear fittings so screens are side-on to both luminaire rows and windows, use some indirect light to lift brightness without a hard source in view, and treat windows as glare sources with solar-control glazing or blinds. Because desk orientation and finishes drive the result, glare has to be resolved alongside the interior layout, not after furniture lands.