Rooftop Grease Containment in North York
Rooftop grease containment is the practice of catching what a kitchen exhaust fan discharges at roof level, before it spreads across the membrane, runs down a parapet, or reaches a storm drain. Every Type 1 exhaust system ends at a fan on a roof, and everything the cleaning misses upstream arrives there eventually. Elite Hood Cleaning North York cleans the fan, the curb and the roof around the discharge, and reports honestly on what is already there.
This usually arrives as a landlord complaint, not a kitchen problem
The grease lands on roofing the tenant does not own, which is why the phone call generally comes from a property manager.
The exhaust fan sits on a curb, and grease-laden vapour leaves through it. Part of that vapour condenses at the fan housing and drains back down the curb. The rest settles on the roof surface downwind of the discharge, in a plume that widens season by season until the area around the curb reads dark and tacky. By then the grease has usually found a low point and started travelling.
Two costs follow. The first is the roof covering. A single-ply membrane, together with the adhesives and welded seams holding it together, is not specified to sit under a petroleum-adjacent contaminant for years at a time. Softening, staining and seam degradation are the visible outcome, and a roofing warranty is generally the invisible one, because most warranties exclude damage from contaminants the building owner allowed to accumulate.
The second is drainage. A roof drains somewhere, and what it carries goes into the building storm system and then into the municipal one. Grease reaching a storm drain is a discharge problem with the building's name on it, and it is considerably more expensive to argue about after the fact than to prevent.
Who pays: tenant or landlord
The answer is in the lease, but the pattern in North York plaza and mixed-use buildings is consistent enough to plan around.
| Tenant vs landlord | Typically the tenant | Typically the landlord or building owner |
|---|---|---|
| The exhaust system serving their kitchen | Cleaning the hood, filters, duct and fan on a schedule | Granting roof access and coordinating it safely |
| The roof surface itself | Rarely, unless the lease says so explicitly | The membrane, the warranty, and any contamination on it |
| Containment devices at the fan | Sometimes, where the lease assigns kitchen equipment | Usually, since they protect the building fabric |
| Storm drain contamination | Contributes the grease | Holds the liability as the property owner |
| Who normally makes the call | Books the kitchen exhaust cleaning | Books the roof assessment after seeing the staining |
Quotes are issued to whoever needs them, and where a job crosses the boundary the report separates the kitchen exhaust work from the roof work so each party can see their own portion. That single act of separation resolves most tenant and landlord disputes about this before they start.
What actually happens at the roof
Roof work is the part of a hood cleaning most likely to be skipped, because it is the part nobody in the kitchen will ever see.
The fan is isolated and locked out before anyone approaches it. Where the fan is hinged or can be safely lifted, it is opened so the blade faces, the housing interior and the discharge throat can be degreased. Where it is seized, corroded, or bolted down without a hinge, it is left alone and reported, because forcing a fan open damages equipment nobody here is qualified to repair.
The curb is then cleaned inside and out, and this matters more than it sounds: the curb is where liquid grease running back down the ductwork collects, and a full curb is what feeds the plume onto the membrane. Any containment already fitted, whether a proprietary grease box, an absorbent pad system or a homemade tray, is emptied where practical and its condition reported. A containment device full to the brim has stopped working and is now a reservoir.
Finally the roof surface around the discharge is cleaned within the limits of what is safe for the membrane, and photographed. Where staining has gone beyond what cleaning can address, that is said plainly in the report rather than papered over, because a roofing contractor needs to see it and the building owner needs to know before the next warranty conversation.
Check first: If a containment tray at the fan has never been emptied, the roof has been protected by an already-full container for however long that has been true.
North York roofs, specifically
Access is the variable that changes the job, and this borough has two distinct situations.
Strip plazas along Sheppard, Finch, Wilson, Dufferin and Bathurst put a low, flat, shared roof over a row of tenants. Fans from several kitchens sit within metres of each other, drainage crosses tenancy lines, and it is frequently impossible to tell from the ground which plume belongs to which unit. On these buildings the useful deliverable is a photographed survey identifying each fan and the condition around it, because that is what lets a property manager apportion anything fairly.
Mixed-use towers around Yonge and Sheppard and Yonge and Finch are the other case. The kitchen is at grade, the fan is many storeys up, and the roof is a managed space with its own access procedure, anchor points and notice requirements. Work there is booked around building management rather than around the restaurant, which is why roof access is confirmed before a visit is scheduled rather than after.
In both cases the practical advice is the same. Have the roof looked at in daylight before booking overnight work, because a roof assessed at two in the morning by torchlight is an assessment nobody should be relying on.
Common questions about rooftop grease
Is the roof included in a normal hood cleaning?
The fan, the fan housing and the curb are included in every exhaust system clean, because they are part of the system. Cleaning the roof surface itself, or dealing with an accumulated plume that has been building for years, is assessed separately since it is building work rather than kitchen work and is often the owner's cost rather than the tenant's.
Do you supply and fit grease containment devices?
Containment devices already fitted are cleaned, emptied where practical and reported on. Elite Hood Cleaning North York does not install rooftop equipment, alter fan mountings or modify a roof, because that is roofing and mechanical work. Where a site needs containment fitted, the report documents the situation so the right trade can quote it.
Can grease damage really void a roofing warranty?
Roofing warranties commonly exclude damage caused by contaminants the owner permitted to accumulate, and kitchen exhaust grease is a well-known example. The specific wording varies by manufacturer and by contract, so the answer for your building is in your own warranty document. What is consistent is that dated photographs showing the roof was being cleaned help the conversation and their absence hurts it.
The fan is on a roof we cannot access. What then?
Access has to be arranged before work is scheduled. In managed buildings that means building management, a notice period, and sometimes a permit and anchor points. In plazas it means the landlord. Nothing is attempted from an unsafe position, and a fan that cannot be reached safely is documented as not cleaned rather than quietly signed off.
Why is there grease on the roof if we clean the hood regularly?
Because some carryover to the fan is normal even on a well-maintained system, and it accumulates between visits. A large plume on a kitchen with a genuine cleaning history usually points to something else: filters that are the wrong type, a missing filter creating a bypass, or duct sections nobody can reach. The filter page covers the first two.
Can this be done in winter?
Roof work in a Toronto winter is scheduled around conditions rather than around a date. Ice, snow load and wind make some roofs unsafe on some days, and where that is the case the roof portion is deferred and the interior work goes ahead. A contractor willing to send someone onto an icy plaza roof at night to hold a booking is telling you something about how they run jobs.