A rooftop unit replacement in the GTA runs $14,000–$22,000 installed for a 5-ton single-zone packaged unit and $22,000–$35,000 for a 10-ton, plus crane mobilization at $1,500–$5,000 a lift day. Rooftop equipment lasts 15–20 years, so the units that went up during the 2005–2010 commercial build-out are reaching that line now — often several on the same roof, within a season or two of each other.
That timing is the planning problem worth solving. Strip plazas along Steeles, offices off Bloor and light industrial in Mississauga all tend to carry a matched set of RTUs of the same vintage, and replacing them one emergency at a time costs more than grouping the work. What follows is the cost, permit, crane and scheduling detail a property manager needs before writing the capital request.
RTU Replacement Cost in the GTA (2026)
- Single-zone packaged RTU, 5-ton: $14,000 – $22,000 installed
- Single-zone packaged RTU, 10-ton: $22,000 – $35,000 installed
- High-efficiency condensing gas RTU, 7.5-ton: $25,000 – $38,000 installed (qualifies for Enbridge commercial incentives)
- Variable-capacity RTU with economizer, 10-ton: $32,000 – $48,000 installed
- Make-up air unit (MAU), 5,000 CFM: $30,000 – $55,000 installed
- Crane mobilization (added to all of above): $1,500 – $5,000 per crane day depending on building height and access
Why bundling units cuts the per-unit price
Crane mobilization is a fixed cost that does not care how many units you swap. The rigging crew, the lane closure, the swing-radius plan and the traffic control cost the same whether one RTU comes off the roof or four, so every additional unit lifted in that window dilutes the charge across more equipment.
That is the argument for replacing on a planned cycle rather than one failure at a time. A plaza with five units of the same vintage will lose them within a few years of each other; grouping the two or three that are furthest gone into one lift beats paying for a separate mobilization each August. It also gives you one set of permits, one tenant notice and one commissioning visit.
The curb is the detail that derails schedules
A new unit rarely matches the footprint of the one that came off, so the roof curb either gets adapted or rebuilt. A curb adapter is fabricated to bridge the old opening to the new unit's base, and it has to be measured from the actual curb rather than from a drawing set that may not reflect a 1990s retrofit.
Get the curb measured during the quote, not on lift day. The other roof-side items worth confirming in advance are the gas piping and shutoff, the electrical disconnect and its rating, the condensate route, and whether the roofing membrane needs a patch and flashing detail where the old curb sat.
Scheduling Logistics That Minimize Tenant Disruption
- Spring (April-May) and fall (October-November) are ideal — moderate weather means tenants can tolerate brief HVAC outages
- Summer (July-August) is the worst time — peak cooling demand makes any outage catastrophic for tenants
- Winter (Dec-Feb) is acceptable for cooling-dominated RTUs (offices) but risky for heating-dominated ones
- Early-morning crane work (5–8 AM) is often city-permitted with advance notice and has the bonus of catching tenants before they arrive
- Plan a 4-hour minimum outage window per unit; schedule as overnight or weekend work for retail / restaurant tenants
- Notify tenants 2 weeks in advance with specific date, time window, and contingency for delay
Permits, inspections and compliance
- A building permit is required for the replacement, and permit costs vary by municipality — Toronto, Halton Region and the City of Hamilton all run their own process and timelines
- Any unit with a gas heating section is TSSA work: the gas connection and its inspection have to be done by a licensed technician
- Electrical disconnection and reconnection falls under ESA rules, and the disconnect rating has to suit the new unit rather than the old one
- Recovered refrigerant from the old unit must be handled by certified technicians and documented, which matters more now that equipment is moving from R-410A to A2L refrigerants such as R-454B
- Check the roof structure before specifying a heavier unit, and expect the question to come up on any building where the framing predates the current unit
- Ask whether the equipment triggers an Environmental Compliance Approval or falls under an exemption — that answer comes from the current provincial guidance, not from a rule of thumb
Commercial incentives: what to check before ordering
Free quotes, written pricing.
Enbridge runs commercial and industrial incentives for qualifying high-efficiency equipment — condensing rooftop units, condensing make-up air, high-efficiency boilers — and Save on Energy runs commercial measures on the electricity side, including controls and building automation. Both are structured by program year.
The trap is timing. Purchase and installation deadlines shift from one program year to the next, and equipment bought before an application is approved can fall outside the window. Confirm the current dates and amounts on the program pages before you release a purchase order, and have the contractor register the project rather than assuming it can be claimed afterwards.
Repair or replace: the decision rule
- Under 10 years old — repair, including for a compressor or board failure, provided the cabinet and coils are sound
- 10 to 15 years — it depends on the part. A cracked heat exchanger ends the conversation; a motor, actuator or board on an otherwise healthy unit is worth fixing
- Over 15 years — plan replacement. Parts availability tightens, and repair spend on a unit that far along rarely returns anything
- Two or more significant failures inside 24 months — replace regardless of age, because you are now buying the same unit twice
- Still running R-22 — replace. Production ended years ago, only reclaimed supply remains, and the price makes any recharge a poor investment
Where the energy savings actually come from
Three places, and the equipment nameplate is only one of them. A current-generation unit cools at a better EER than a 2008 model, a condensing gas section extracts more heat than the atmospheric burner it replaces, and a commissioned economizer brings in outside air on cool days instead of running the compressor.
The economizer is the one that gets skipped. Its damper actuator and outdoor sensor are what let a Toronto office building coast on free cooling through spring and autumn, and a unit installed with the linkage never calibrated loses that benefit quietly for years. Ask for the commissioning report, not just the start-up sheet.
Common Mistakes Property Managers Make
- Awarding on price alone, when the gap between two bids is usually duct sealing, economizer commissioning and controls integration rather than the equipment itself
- Replacing tonnage for tonnage without a load review — original units were frequently oversized, and a right-sized replacement costs less to buy and cycles less
- Leaving the economizer out of the specification, or accepting a unit whose damper linkage was never calibrated at start-up
- Budgeting the equipment but not the curb adapter, the roofing detail, the disconnect or the gas piping — the items that turn a lift day into a change order
- Replacing one unit at a time and paying a fresh crane mobilization each year instead of grouping the lifts
- Handing over the building without a commissioning report, control setpoints and filter sizes documented for whoever maintains the unit next
Keeping the new units out of the emergency queue
A rooftop unit fails on the roof, unattended, usually in the first heat wave. Quarterly filter changes, belt and bearing checks, coil cleaning and an economizer check before each cooling season are what keep a 15-year design life from turning into ten. Rooftop coils in this region also collect road salt and grit off the QEW and Red Hill corridors, which shortens fin life on buildings close to the highway.
For a multi-tenant property, a scheduled program also gives you documentation — dated service reports you can hand to an owner, an insurer or a buyer. That case is set out in why preventive commercial service saves money, and the difference between rooftop and split equipment is covered in RTU vs split system.
Scoping an RTU replacement with us
We work on retail plazas, offices, light industrial and restaurant spaces across the GTA and Hamilton, and a project runs as one package: roof and curb assessment, permits, crane and rigging scheduling, tenant notices, equipment selection, installation, commissioning and the incentive paperwork. Pricing is written before the work, and there are no overtime, weekend or holiday surcharges on the schedule we agree.
See the scope on our commercial HVAC services page, put a program in place through maintenance plans, or contact us with your unit list and roof access details and we will scope it.
Frequently asked questions
How long does an RTU replacement take?
For a straightforward like-for-like swap, plan a single day per unit on the roof: disconnect, lift out, set the new unit on its curb or adapter, reconnect gas and electrical, then commission. The lift itself is a short window inside that day. Curb fabrication, permits and equipment lead time are what stretch the calendar, not the install.
Do tenants have to be out during the work?
No, but they do need notice. The unit serving their space is down for hours rather than minutes, and crane work usually means part of the parking area is closed. Give two weeks' notice with the date, the window and what happens if weather pushes it. Restaurants and retail are usually scheduled outside trading hours.
Can we replace an RTU in winter?
Yes, and it is a reasonable time for cooling-dominated units in offices, since the outage falls on the season the unit is not needed. It is riskier for a unit carrying the building's heat. Spring and autumn remain the easiest windows because a short outage is tolerable in either direction.
Is a rooftop unit worth repairing at 12 years old?
It depends on the part. A cracked heat exchanger or a failed compressor in a unit that age usually points to replacement, while a motor, control board or damper actuator is worth fixing. Weigh the repair against the remaining life and against what the replacement would cut from the energy bill.