If one system decides whether a food buildout lands on budget, it is ventilation. It is usually the largest single mechanical cost, it constrains where the kitchen can go, and it is the thing most likely to make a promising space unworkable.
It is also the system operators understand least at the point they are making the decisions that determine it.
The chain of consequences
Ventilation is not really one decision. It is a chain, and it starts with the menu:
Menu → cooking equipment → hood type → exhaust volume → make-up air volume → duct route → rooftop equipment → structural and electrical load.
Every link is determined by the one before it. That is why “we might add a fryer later” is not a small statement. It can change the hood, the fan, the make-up air unit, the fire suppression, the gas line and the electrical service.
Type 1 versus Type 2 hoods
The distinction that matters most is whether your cooking produces grease-laden vapour.
Type 1 hoods handle grease and smoke — fryers, griddles, charbroilers, ranges, woks, solid fuel. They require grease filters, a fire suppression system, welded grease-tight ductwork, cleanout access and a dedicated exhaust fan. They are the expensive path, and they bring the rest of the mechanical scope with them.
Type 2 hoods handle heat, steam and odour without grease — dishwashers, ovens in some configurations, steam equipment. Simpler construction, no fire suppression requirement, lighter ductwork. Substantially cheaper.
A café serving pastries and coffee with a Type 2 condensate hood over a dish machine is in a completely different budget from a kitchen with a Type 1 hood over a cooking line. This single distinction can be the difference between a modest fit-out and a major mechanical project, which is why the menu needs to be settled before the design starts.
Make-up air is the part people miss
A hood removes a large volume of air from the kitchen. That air has to be replaced, or the space goes into negative pressure — doors become hard to open, the hood stops capturing properly, other appliances can be affected, and in winter the kitchen becomes unworkable.
So you need make-up air: replacement air, brought in from outside, and tempered so you are not blowing sub-zero air across a cooking line in February.
Two things about make-up air catch operators out.
It is frequently the larger cost. A tempered make-up air unit has to heat a substantial volume of outdoor air. In an Ontario climate, that is a real piece of equipment with a real gas or electrical load, and it needs somewhere to sit.
It needs a physical route. The air has to come from outside and get to the kitchen. In a mid-block unit with no exterior wall and no straightforward roof access, that route may not exist without significant work. This is one of the most common reasons a space that looks fine on a walkthrough turns out not to be.
The route to the roof
Type 1 exhaust duct has to run from the hood to a fan, almost always on the roof, and it has rules about how it gets there — grease-tight welded construction, clearances to combustibles, access for cleaning, and a discharge point positioned so it does not re-enter the building or vent onto a neighbour.
What this means practically:
- There must be a path. Through the ceiling, through any floors above, to the roof. In a multi-tenant building with occupied space above, that path may need to be negotiated, boxed and fire-rated — or may not exist.
- The roof has to carry the equipment. Exhaust fan, make-up air unit and any HVAC. That is real weight, and sometimes it means structural reinforcement.
- You need permission to penetrate. Which is a lease question, a roof warranty question, and a scheduling question.
- Discharge location matters. Distance from intakes, property lines and neighbouring windows is regulated, and residential neighbours make it harder.
Fire suppression
A Type 1 hood requires a fire suppression system over the cooking line — nozzles positioned for the specific appliances beneath, tied to a gas shut-off and to the building’s alarm.
Two consequences worth knowing:
It is designed for your exact equipment layout. Nozzles are positioned for specific appliances in specific positions. Move the fryer after installation and the system has to be re-engineered. This is a real cost and a real inspection issue.
It is inspected, and it holds occupancy. The fire final is part of the chain that leads to your occupancy permit.
What actually moves the cost
In rough order of impact:
| Decision | Effect |
|---|---|
| Type 1 versus Type 2 | The single largest fork. Type 1 brings suppression, welded duct and a bigger fan. |
| Length of cooking line | Hood length drives exhaust volume, which drives make-up air, which drives everything. |
| Solid fuel cooking | Wood or charcoal adds separate duct, spark arrest and cleaning requirements. |
| Distance to the roof | Duct run length, floors to pass through, and how much boxing and rating is needed. |
| Existing infrastructure | A second-generation space with a compatible hood already installed is dramatically cheaper. |
| Structural capacity | Reinforcement for rooftop equipment is a cost nobody budgets at the start. |
| Gas and electrical load | Make-up air heating and the exhaust fan both add to services you may need to upgrade. |
Questions worth asking early
- Does my menu require a Type 1 hood, or can it be done with Type 2?
- What exhaust volume does that hood need, and what make-up air volume does that imply?
- Where does the duct run, and what does it pass through?
- Can the roof carry the equipment, and am I allowed to penetrate it?
- Is there an existing hood, and is it the right type, size and condition for my line?
- What does the make-up air unit need for gas or electrical, and does the service support it?
If you are looking at a second-generation space with a hood already in place, the questions become: is it the right type, is it long enough for your line, does it have current certification, and has the duct been cleaned and inspected? An existing hood is a genuine asset — but only if it matches what you intend to cook under it.
The practical takeaway
Ventilation rewards deciding early and punishes deciding late. The menu sets the hood, the hood sets the mechanical scope, and the mechanical scope is a large share of the budget.
If you are still weighing spaces, this is the system to have assessed before you sign, because it is the one most likely to turn an affordable-looking unit into an expensive one. And if you are weighing menu options, understand that a single piece of equipment can move you across the Type 1 line and take the budget with it.
