Office Lights: 2x2 vs 2x4 Panels and LED Retrofit Options

Offices, especially in Ontario live under troffers and flat panels. If you are planning a lighting upgrade, the first fork in the road is usually 2x2 vs 2x4 and retrofit vs replace. Get those right and everything else, comfort, energy, rebates, and ROI, falls into place.

Before we dive in, if you want a quick visual of how fast panels transform offices, see our quick read on 2x4 LED flat panel lights.

TL;DR for office lights

• Most offices do best with 2x4 LED flat panels, 35–45 W, 4000 K, CRI ≥ 80, UGR ≤ 19, DLC listed, 0–10 V dimming, PF ≥ 0.90.

• Smaller rooms and clinics often prefer 2x2 panels, 25–35 W, same specs as above, for tighter, more uniform grids.

• Aim for 300–500 lux on desks, flicker < 5%, THD < 20%, and a 5–10 year warranty.

• In Ontario, rebates for office lights are currently available only through the Save on Energy Instant Rebate program via participating distributors—no custom or prescriptive pathways for this scope.

• Ready to price it properly? Use our Instant Lighting Quote to get a supply and install estimate aligned to your ceiling grid and hours of use.

How to choose office lights

Ceiling grid type and plenum constraints

Credit: Decorapick

Start by looking up—literally. Most offices here use T-bar 2x4 or 2x2 tiles. Measure plenum depth (the space above the tiles) and peek for ducts, sprinklers, cable trays, or return air. A thin flat panel (often 1.5–2.5 in thick) slides into tight plenums where retrofit kits might clash with ductwork.

Example: A 1980s Mississauga office with shallow plenum and a maze of cabling moved to 2x4 panels during a furniture refresh; install time dropped to ~20–25 minutes per opening, no cutting, no dust.

Visual comfort: glare control that people actually feel

If staff say the lighting is “bright but doesn’t feel better,” you’re staring at glare, not a lumen shortage. Look for panels with micro-prismatic or low-UGR diffusers that soften high-angle brightness so monitors stay readable. In open offices, aim for ~350–400 lux on the desk and keep UGR around 19. Corridors and print areas are fine closer to 200–300 lux.

Tip: Before adding dimmers everywhere, fix the optic first. A proper diffuser often ends complaints without touching wattage.

Colour quality: CRI and the right CCT for your brand

CRI 80+ is solid for most floors; CRI 90 is worth it for clinics, design reviews, or any space where accurate colours matter. Colour temperature sets mood: 4000 K reads clean and neutral for open areas; 3500 K flatters faces in meeting rooms and on video calls. The key is consistency—pick one CCT per floor so the ceiling doesn’t look patchy from zone to zone.

Flicker and driver quality: comfort you can’t see—but will notice

Good drivers cut invisible flicker that contributes to fatigue and complaints after long screen time. Specify <5% flicker across the dimming range and 0–10 V control down to 10% (or 1% if you’re setting scenes). Keep THD under 20%, and choose drivers with 50,000–100,000-hour ratings so you’re not up a ladder again for a decade of typical office hours.

Efficiency and listings: DLC, power factor, and warranty

DLC-listed lamps and luminaires help with distributor rebates and ensure you’re getting modern efficacy—~120–140 lm/W is a realistic range for quality panels today. Look for power factor ≥ 0.90, CSA/ULc, and a 5–10 year warranty. Those three lines on a spec sheet are what keep your operating budget predictable.

A quick spec snapshot (use this as your baseline)

Topic	Practical target for Ontario offices
Desk illuminance	300–500 lux (350–400 lux is a happy middle)
Glare	UGR ~19 in open offices with screens
Colour	4000 K open areas; 3500 K meeting rooms; CRI 80+ (90 in clinic/design)
Dimming & flicker	0–10 V; <5% flicker; THD <20%
Efficacy & warranty	120–140 lm/W; 5–10 year warranty

If you’re still weighing whether to reuse housings or drop in new panels, this decision tree—LED Retrofit vs New LED Fixture: When to Retrofit and When to Replace—walks through downtime, ceiling cleanliness, and lifecycle cost so you can choose with confidence.

2x2 vs 2x4, what fits your space

Credit: cooperlighting

The size you choose should follow the room, not the other way around. Think about room width, ceiling height, screen placement, and how often people look across the space rather than down at paper. In open offices, a 2x4 often feels calmer because you need fewer fixtures to reach target light levels. In smaller rooms and clinics, a 2x2 grid lands more uniform light without washing walls and screens.

Typical use cases you can trust

• Open office and bullpens. 2x4 panels at 35 to 45 watts deliver a clean, neutral ceiling with fewer tiles glowing at once.

• Meeting rooms and huddle spaces. Either size works, but many teams prefer 2x2 for tighter control and scene presets.

• Corridors and copy areas. 2x4 at slightly lower output keeps maintenance simple.

• Clinics, exam rooms, classrooms. 2x2 provides even coverage in compact rooms and pairs well with higher CRI.

Light distribution and spacing rules of thumb

Think in simple grids. At a nine foot ceiling, a good 2x4 panel will comfortably space at 8 to 10 feet on centre. A comparable 2x2 grid prefers 6 to 8 feet on centre. Aim for 350 to 400 lux on desks in open areas and keep the minimum to average uniformity around 0.6 or better so the space reads even to the eye. If monitors dominate, favour optics that control high angle brightness and keep UGR near 19.

Ceiling height and uniformity targets

Ceilings 8 to 9 feet tall are friendly to either size. At 10 to 12 feet, 2x4 panels or higher output 2x2s help avoid dark lanes between fixtures. Long, narrow rooms benefit from a slightly tighter row spacing to keep walls bright enough for video calls and wayfinding. When in doubt, mock up one row and meter the desk line at one metre intervals. Five minutes of measuring beats five years of complaints.

Quick selector you can share with your team

Room type	Best default	Output target per fixture	Typical spacing	Why it works
Open office, 9 to 10 ft ceiling	2x4	4,000 to 5,000 lumens	8 to 10 ft O.C.	Fewer fixtures, smoother ceiling
Private offices, meeting rooms	2x2	3,000 to 4,000 lumens	6 to 8 ft O.C.	Tighter grid, good for scenes
Corridors and support spaces	2x4	3,000 to 4,000 lumens	10 to 12 ft O.C.	Simple run, easy maintenance
Clinics and classrooms	2x2	3,500 to 4,500 lumens	6 to 8 ft O.C.	Uniform light, higher CRI options

Retrofit options for existing troffers

Most Ontario offices already have fluorescent troffers. You can keep the housing and upgrade the light source, or you can swap in a full LED panel. The right answer depends on plenum depth, how clean you want the ceiling to look, and how fast you need the install to go.

T8 LED tubes, pros and cons

If you need the fastest, lowest cost lift, LED tubes are the entry point. A two tube or three tube layout often replaces a four lamp T8 and still meets target light levels.

Why people choose tubes

• Lower material cost and quick labour in familiar housings

• Minimal disruption to furniture and ceiling tiles

• Good choice for back rooms and interim upgrades

What to watch

• Ballast compatibility versus line voltage bypass adds decision complexity

• Optics rely on the old troffer, which can mean more glare and a dated look

• Mixed ballasts across a building accelerate future maintenance calls

Typical Ontario ranges

Material 40 to 90 dollars per opening, labour 25 to 60 dollars, install 15 to 25 minutes for ballast compatible, 25 to 40 minutes for line voltage. Savings often land 40 to 60 percent versus four lamp fluorescent.

For deeper guidance, use our T8 LED Tube Replacement Guide for Commercial Buildings in Ontario.

Troffer retrofit kits, new optical tray in the old housing

Retrofit kits replace the old lamps and reflector with a new LED light engine and diffuser while keeping the metal housing in place. The result looks like a panel from below.

Why people choose kits

• Modern diffuser for better glare control and uniformity

• Cleaner appearance without touching the grid

• Good middle ground when panels will not fit the plenum

What to watch

• More parts and steps than tubes

• Slightly longer install and more debris to handle

• Verify 347 volt compatibility, common in Canadian buildings

Typical Ontario ranges

Material 90 to 160 dollars per opening, labour 45 to 90 dollars, install 30 to 45 minutes. Efficacy commonly lands 120 to 135 lumens per watt with a five to ten year warranty.

Full LED flat panel replacement, when it is best

Panels remove the old housing and slide in a thin, sealed luminaire. It is the cleanest visual and usually the most straightforward long term.

Why people choose panels

• Fresh ceiling, higher uniformity, and low flicker drivers

• Light weight, often 6 to 10 pounds, which is friendly to older grids

• Fast installs in empty floors during lease turns

What to watch

• Need clear access above the grid for the driver box and junction

• Check air handling use, some plenums require rated panels

• Coordinate photometric layout if changing size or row spacing

Typical Ontario ranges

Material 110 to 220 dollars per panel depending on size and output, labour 30 to 60 dollars, install 20 to 30 minutes in open areas, longer in live spaces. Efficacy often 125 to 140 lumens per watt, with dimming to 10 percent or 1 percent on better models.

Retrofit versus replacement checklist

Use this short list in a walkthrough. If you answer yes to most items in a column, you have your path.

Choose tubes

• You need a stopgap this quarter

• Plenum access is blocked by duct or cable trays

• Aesthetic refresh is not required in these rooms

Choose retrofit kits

• You want a modern look without removing housings

• Plenum depth is tight but workable

• You want better uniformity and lower glare than tubes

Choose full panels

• You want the cleanest ceiling and fastest future maintenance

• The plenum is clear and the grid is in decent shape

• You plan to add controls and scenes across the floor

Quick comparison, retrofit kit versus flat panel

Item	Retrofit kit	LED flat panel
Appearance from below	Looks like a new panel, housing stays above	Clean, seamless, no old metal
Install time in live space	30 to 45 minutes	20 to 30 minutes
Glare control and uniformity	Good with quality diffuser	Very good with low UGR options
Plenum requirements	Moderate depth, housing remains	Low profile, needs junction access
Long term maintenance	More parts remain in ceiling	Fewer parts, simple swap if needed

If you want a full decision tree that weighs downtime, ceiling cleanliness, and lifecycle cost, our guide on LED retrofit versus new LED fixture covers the tradeoffs and includes real project photos.

Controls that cut operating hours

Smart controls quietly reduce how long lights stay on without asking people to think about switches. In Ontario offices this is where many projects unlock a second wave of savings after the fixture swap.

Occupancy sensors for open offices, meeting rooms, and washrooms

Occupancy sensing trims hours where people come and go.What to expect

• Open office zones often see a 15 to 25 percent reduction in annual run time

• Meeting rooms can see 30 to 40 percent because lights no longer sit on between bookings

• Washrooms and copy rooms typically land in the 40 percent range

How to set it up well

• Use area sensors for open office bays and seat count sensors only where desks are fixed

• Pair with a gentle time out like 10 to 15 minutes so lights do not bounce on and off

• Add vacancy mode in small rooms so lights come on only when needed

Daylight harvesting on perimeter zones

Perimeter rows near windows can dim during bright hours while the rest of the floor stays steady.

What to expect

• A realistic 10 to 20 percent reduction in energy on those rows

• Better visual balance at the glass line because the ceiling is not overpowered by daylight

How to set it up well

• Split the first one or two rows into their own control zone

• Calibrate once in full sun and once on a cloudy day to capture a stable midpoint

Time scheduling and scene presets for boardrooms

Schedules cover nights and weekends so nothing stays on by accident. Scene presets keep meetings simple.

What to expect

• A further 10 to 15 percent reduction in total hours for most floors

• Fewer complaints in boardrooms when you provide three simple presets: present, video, and clean up

How to set it up well

• Tie schedules to your access system or janitorial hours where possible

• Give facilities an override button with a clear one hour timer

Networked controls for multi tenant floors and dashboards

Credit: Industrialcommerciallighting

When your office spans multiple floors, networked controls pay off in visibility and consistency.

What to expect

• Portfolio level schedules and global holidays applied once

• Dashboards that show hours of use by zone and help find always on problem areas

Budget guidance

• Standalone wall sensors are the least expensive per room

• Room based wireless kits sit in the middle

• Full networked controls add cost per fixture plus commissioning but return better coordination at scale

Cost ranges and ROI for office lights

Every building is different, but the ranges below reflect what we see across Ontario for typical two by two and two by four upgrades in occupied offices. Use them as planning guardrails, then run your floor through our calculators to refine.

Typical material and labour by option

Option	Material per opening	Labour per opening	Typical install time	Notes you can act on
T8 LED tubes two or three lamps	40 to 90 CAD	25 to 60 CAD	15 to 25 minutes for ballast compatible or 25 to 40 minutes for line voltage	Fastest lift, good for back rooms and interim upgrades
Troffer retrofit kit new optical tray	90 to 160 CAD	45 to 90 CAD	30 to 45 minutes	Cleaner look and better glare control while keeping housings
LED flat panel two by four	110 to 220 CAD	30 to 60 CAD	20 to 30 minutes in open areas	Fresh ceiling, simple future maintenance
LED flat panel two by two	100 to 200 CAD	30 to 60 CAD	20 to 30 minutes	Popular in clinics and small rooms
Occupancy sensor standalone	50 to 120 CAD	40 to 80 CAD	30 to 60 minutes	Choose vacancy mode for small rooms
Daylight sensor per perimeter zone	80 to 150 CAD	60 to 120 CAD	45 to 90 minutes	Split first one or two rows near glass
Networked control node per fixture	25 to 60 CAD	15 to 35 CAD	10 to 20 minutes	Add commissioning budget for large floors

Use the Lighting Retrofit Savings Calculator if you want a quick payback view that reflects your hours and electricity rate. For ongoing expenses like cleaning and relamping, the Lighting Operating Cost Calculator shows where controls reduce cost beyond energy alone.

Energy savings from fluorescent to LED a simple example

Starting point

A floor has one hundred two by four fluorescent troffers at about 96 watts each. You replace them with 40 watt LED panels. The floor runs about 3,000 hours per year. Your blended electricity rate is 0.16 CAD per kWh.

Energy calculation

• Watts saved per fixture equals 56

• Annual kWh saved per fixture equals 56 multiplied by 3,000 divided by 1,000 which is 168 kWh

• Annual dollar savings per fixture equals 168 multiplied by 0.16 which is 26.88 CAD

• Annual dollar savings for one hundred fixtures equals about 2,688 CAD

Add basic controls

Now add occupancy sensing that trims run time by 20 percent in open areas. LED consumption drops from 40 watts at 3,000 hours to 40 watts at 2,400 hours.

• New annual kWh per fixture equals 96

• Annual dollar savings per fixture versus the old fluorescent now equals 35.52 CAD

• Annual dollar savings for one hundred fixtures rises to about 3,552 CAD

These are conservative numbers. If your starting point is a tired three lamp or four lamp troffer with poor optics, or if your hours run longer than a standard office schedule, your savings rise quickly.

Maintenance savings and cleaner ceilings after a panel swap

Fluorescent lamps and yellowed lenses add hidden cost. Crews spend time swapping lamps, wiping dust out of reflectors, and hunting ballast failures. LED panels and quality retrofit kits remove most of that.

Where you save

• Fewer service calls because the driver is rated for long life and the diffuser is sealed

• Less ceiling dust and fewer trips up a ladder which improves safety metrics

• Standardized parts which speeds future swaps

A simple way to value this is to tally last year’s relamp and ballast invoices, then assume you keep only a small fraction post upgrade. Many offices see another 5 to 10 CAD per fixture per year in avoided maintenance, which shortens payback when added to the energy math above.

Rebates in Ontario for office lighting

Rebates in Ontario are currently delivered at the counter through the Save on Energy Instant Rebate program. There is no custom path and no prescriptive path for this scope. That means the discount is applied on your invoice when you buy through a participating distributor, as long as the product is on the eligible list.

Which office lights usually qualify

Most rebates favour efficient, listed products that are common in offices.

• LED flat panels that are listed on DLC with 0 to 10 volt dimming

• Troffer retrofit kits with high quality diffusers and DLC listing

• LED tubes where eligible models are listed and installed to program rules

• Basic standalone controls such as occupancy sensors and daylight sensors

What to check on the quote

• DLC listing noted by model or DLC ID

• Power factor at or above 0.90 and efficacy in a modern range

• Clear quantities by fixture size such as 2 by 2 and 2 by 4

• Controls listed as separate line items if you plan to claim them

If you are planning networked controls across many rooms, assume the Instant Rebate will not cover the full system. Treat it as an energy savings decision first and a small incentive second.

Pre approval steps and documents

There is no formal pre approval for the Instant Rebate, but a short checklist keeps you on track.

• Choose a participating distributor and ask them to apply Save on Energy Instant discounts

• Confirm each product is eligible and listed before you place the order

• Put your business name and site address on the quote and the final invoice

• Keep the invoice, the model list, and photos of a few installed fixtures for your records

If you want to see rough incentive values before you call a distributor, try our quick Lighting Rebate Estimator. It shows typical discounts for panels, retrofit kits, tubes, and basic sensors so you can plan budgets and approvals with fewer surprises.

Use the Lighting Rebate Estimator to preview incentives

Run one floor through the tool with simple inputs such as fixture count, size, and whether you are adding occupancy or daylight sensors. You will get a ballpark total and a per fixture view you can compare to supplier quotes.

Health and productivity considerations

Good office lights do not just reduce kilowatt hours. They help people see screens clearly, reduce fatigue, and make rooms feel calm. The following three choices move the needle the most.

Avoiding glare and veiling reflections on screens

Credit: hokasu

Glare is the top complaint in modern offices. The room reads bright but screens feel harder to read. You can prevent this with better optics and a modest target for desk light levels.

• Choose panels or retrofit kits with micro prismatic diffusers and a low UGR rating around 19

• Aim for about 350 to 400 lux on the workplane in open offices

• Keep high angle brightness under control so the ceiling does not reflect on monitors

A quick test is to lower the output by ten percent in one bay. If comfort improves, you are fighting glare and not a lack of light.

Task and ambient strategy for meeting rooms and focus areas

Rooms with many uses benefit from two or three simple scenes. People present better and video calls look cleaner when the wall behind the speaker is gently lit and the ceiling is not blasting the table.

• Ambient scene for general use at about 300 to 350 lux

• Presentation scene that dims the row above the screen and lifts the wall behind the speaker

• Video scene that softens the ceiling and keeps faces natural for cameras

You can do this with inexpensive 0 to 10 volt controls and a small room controller. If you later upgrade to networked controls, you can keep the scenes and expand them across more rooms.

Colour temperature guidance for comfort through the day

Colour temperature sets the tone of the space. The safest default for Ontario offices is 4000 K in open areas. Many teams prefer 3500 K in meeting rooms so faces look natural on camera and in person.

• Pick one colour temperature per floor to keep the ceiling consistent

• Use CRI 90 in clinics and colour sensitive spaces, CRI 80 works well for most other areas

• If you renovate in phases, label boxes and fixtures by colour temperature to avoid mixing

Small choices like these keep complaints down and make offices feel modern without a premium product list.

Conclusion

Choosing office lights is simpler when you follow the room. Pick a size that fits the grid and the way people use the space, then choose optics and controls that keep screens comfortable and hours low. For many Ontario floors the winning formula is a clean 2x4 LED panel at neutral colour temperature with low glare, plus occupancy sensing in open areas and daylight dimming at the windows. The result is a calmer ceiling, fewer service calls, and a clear payback that finance can accept.

If you want help mapping one floor with real counts and a practical schedule, start a free office lighting audit. If you already know your fixture sizes, you can get pricing through our Instant Lighting Quote and we will align it to the Save on Energy Instant Rebate where eligible.

FAQ

1) Which is better for most offices, 2x2 or 2x4 panels

Most open offices land on 2x4 because you need fewer fixtures to reach target light levels and the ceiling looks calmer. Smaller rooms and clinics often prefer 2x2 for tighter spacing and very even light. If your plenum is shallow, thin flat panels fit where older housings do not. For a quick visual of a fast swap, see our note on 2x4 inch LED flat panels.

2) What colour temperature and CRI should we choose

Use 4000 K in open areas for a clean neutral look. Many teams pick 3500 K in meeting rooms so faces look natural on camera. CRI 80 suits most offices. Step to CRI 90 in clinics and colour sensitive rooms. Keep one colour per floor to avoid a patchwork ceiling.

3) How much energy can we save by moving from fluorescent to panels

A common change is from a four lamp troffer at about 96 watts to a 2x4 panel near 40 watts. At 3,000 hours per year and a blended rate around 0.16 dollars per kWh, the annual saving is about 27 dollars per fixture before controls. Add occupancy sensing and daylight dimming and total savings often rise by another 15 to 30 percent depending on the space mix.

4) Are rebates available for office lighting in Ontario right now

Yes through the Save on Energy Instant Rebate program at participating distributors. For this scope there is no custom path and no prescriptive path. The discount appears on your invoice when the quoted products are eligible. Ask your supplier to confirm DLC listing and model numbers before you order.

5) Should we retrofit the existing troffers or replace them with flat panels

Retrofit tubes are the fastest and least expensive. Retrofit kits give you a modern diffuser while keeping the housing. Full panels give you the cleanest ceiling and the simplest future maintenance. If you want a deeper walk through of the tradeoffs, start here: LED Retrofit vs New LED Fixture. If your renovation includes reception or boardrooms and you are considering pot lights, this primer will help with options and pricing for commercial spaces in Ontario: Potlight installation cost guide.