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Bar/Tavern help

Sean

Registered User
Joined
Aug 31, 2018
Messages
9
Location
Oregon
I am in the process of opening a Bar/Tavern in Oregon. I will streamline past details to start and can fill in any areas needed. Essentially I’m not required to have a hood system because the equipment I’m using is exempt based off UL 710B I believe is the code. However I’m told I need exhaust for heat and therefor make-up air, which is a challenge in my space. I only need about 400-500 CFMs based off the code math provided. My question is can I just use shutter fans that are about 10-12 inches and 800-1200 CFM fans for both exhaust and and make-up air, or do I have to have a “specific” make up air fan. How big of a duct would be required and what are the rules about them being around and near electrical meters when they expell from the building? I have read the code many times, but not being an engineer myself, I’m not able to make a good interpretation as my building inspector would. Keep in mind building is a 2story 10,000 SQF but I’m only in 2700 of it in lower level, and that means there is an “architect on file” that I have to present information to before inspector. It has made things very difficult cause inspector won’t amswer my questions directly, and architect doesn’t live in my town anymore so he can’t visually see opstacles. Any advice would be greatful. Thank You.
 
Also keep in mind I have had a hard time getting any mechanical company to figure this stuff out for me. They hear exhaust and make up without hood and lose interest. Essentially one company told me, tell me exactly where our path is and then call me.
 
make up air does not have to come from a dedicated unit. Essentially you want to supply as much air into the space as your are exhausting - so that the pressure is neutral.

I would expect that you are already being supplied with outside air (ventilation air) thru a roof top unit or another mechanical unit. You say you only need 400 to 500 cfm of 'make up air' which is not a lot. You might be able to increase the amount of outside air thru that existing unit so that it balances with the total amount of air exhausted. This would probably be the easiest solution if the mechanical unit can handle the additional load to heat/cool that additional 400 -500 cfm. There can be a variety of other solutions to your problem.
 
Sounds like you do need local help

Also sounds like you are required a vent a hood

So what cooking appliances are you planning on having???


Will you also have a dishwasher machine??
 
First thanks for the quick responses! So the current furnace does have to have a co2 sensor installed to bring in fresh air. It’s not in the immediate area of the kitchen but it is all considered one space. The make up and exhaust I’m told have to happen automatically at the same time. Can the current HVAC do that with little work?

As for equipment being used, because a bar is really only 30% of sales as food, I’m going light menu. I’m using a AutoFry machine and a Multichef Oven, along with a panini grill to do what I need. The dishwasher will be an “undercounter” machine which also does not require a hood system as it’s low temp with chemicals. The big deal for me is whether I can run the exhaust and make up air through the wall rather than roof, but there’s tons of electrical meters and things of that sort.
 
I'm not well versed in controls, but i would imagine something could be rigged up. Essentially when the cooking exhaust is running your HVAC system would have to bring in an amount of air to balance with the exhaust, and when the cooking exhaust is not operating, the control would be given back to the CO2 sensor to bring in (a lower) quantity of air based on the pollutants in ambient air. Weather this setup is possible, is a question best answered by a local technician / designer.

as far as the 2nd part, if you can run the make up air/exhaust thru the wall rather than the roof, the short answer is yes. the opening location for intake is regulated by section 401.4 in the international mechanical code, and the exhaust location - if not using a hood - by section 501.3. & possibly 506.3.13, 506.4, 506.5 - although if you are not installing a hood i think the latter sections are not applicable.

I don't know if Oregon/local municipality modifies the standard provisions of IMC but this would be a good starting point.
 
CO2

Carbon Dioxide


CO

Carbon Monoxide


If you have CO2 tank for soda or beer, depending on codes adopted, CO2 detector and alarm is sometimes required.
 
The vent less deep fat fryer may require a specific amount of make up air
Per the manufacture requirements

Check all the install requirements
 
the CO2 detector in the HVAC unit is used as a sensor in demand control ventilation - which determines the amount of outside (fresh) air incoming into the system, and not intended to be used as an alarm.

basic principle is
less people = less co2 produced = less outside air required = energy savings from less outdoor air being tempered
 
the CO2 detector in the HVAC unit is used as a sensor in demand control ventilation - which determines the amount of outside (fresh) air incoming into the system, and not intended to be used as an alarm.

basic principle is
less people = less co2 produced = less outside air required = energy savings from less outdoor air being tempered



So what Code section do you have

CO2 detector in the hvac

Can you post the number section

Or link to it
 
Thanks again for responses. Your right in that it’s a co2 defector to bring in fresh air as stated. I read the intake code and was stuck on exactly what this part was saying:

401.4 #3
“Intake openings shall be located not less than 3 feet (914 mm) below contaminant sources where such sources are located within 10 feet (3048 mm) of the opening.”

What exactly is a contaminant source? Gas or something of the sort I assume?

Also this one
501.3.1 #2
For other product-conveying outlets: 10 feet (3048 mm) from the property lines; 3 feet (914 mm) from exterior walls and roofs; 10 feet (3048 mm) from operable openings into buildings; 10 feet (3048 mm) above adjoining grade.”

When it says from exterior walls, is this saying it much stick out from exterior by 3 feet?
Thanks again
 
Kitchen exhaust

Other exhausts of similar nature?

Neighbors exhaust system
 
Welcome to the forum.

Speaking on behalf of anyone giving you free advice, there is no warranty or liability for what you decide to do with that advice.
Architects and engineers get paid to prevent smart people from doing something stupid. But when stupid people insist on doing something stupid, then they give a polite response to say that they are not interested in the project. And I understand that all projects (without exception) have financial and physical limitations. Kudos to you for reading the related code sections.

Starting with the existing HVAC system, was it originally designed and used for a bar/tavern? A mechanical engineer wants to know that a 2,700 square foot bar full of people will be comfortable with adequate fresh air when that tavern is full of people at maximum capacity. Sure - a twelve inch diameter fresh air intake (through the wall) could be tied into the return air duct for this existing HVAC unit. When this existing HVAC unit is interlocked with your deep fat fryer and associated heat exhaust vent, the make up air is sucked into the building and then either cooled or heated before replacing the greasy air and smoke from the fryer.

My inspectors and I have also looked carefully at deep fat fryers with tested and approved recirculating systems in accordance with UL 710B. We have had folks install these without a permit. While it is wrong for these to be incorporated without a permit, it has offered us the ample opportunity to examine their performance. They get greasy unless the grease filters are cleaned on a routine basis. And when they are not cleaned on a routine basis, they become dangerous if a fire should start. Without a Type 1 exhaust hood, there is no automatic fire extinguishing system. And when a 10,000 S.F. building is totally destroyed, we can all say that there was no minimum code requirement related to the electrical meter and close proximity of the greasy exhaust vent. But that's all okay because we have "an architect on file".

As already discussed, your exhaust system needs to be interlocked with the HVAC system (and associated fresh air intake).
Your CO and CO2 detectors need to be interlocked with the same HVAC system (and associated fresh air intake).
Determining whether-or-not the amount of fresh air intake will be adequate is typically the responsibility of the mechanical engineer.
I pray that you find an architect with his belly up to the bar so that you do not need to reach out too far to find one.

Welcome to the forum.
 
Good of you to share with him.

As to his 3' question, it means from other buildings or overhangs.
Same with windows (if any) on the floor above or adjacent to the opening.
 
Thanks again! I’m response to this
“Without a Type 1 exhaust hood, there is no automatic fire extinguishing system.”

The AutoFry machine is actually an enclosed fryer system that has a ANSUL sprinkler system inside of it for that very reason, which is why it is exempt from needing a type 1 hood system. They were created for the industry to help from having to pay 10s of thousands of dollars for a hood system that isn’t nessesary for the amount of volume of food my business will be doing. Pretty nifty machines actually!
 
Another question.
Can exaust and intake ducting be outside the side of building, and then run up to gain extra clearance? Or do that have to come out where the actual end of vent will be?if I could go up externally I would be able to easily gain clearance. I’m sure the building owner would even let me build some kind of wood cover so it looks as part of building construction. This would be an easily solution for me, which means it’s probably not allowed haha.
 
Welcome to the forum.


Starting with the existing HVAC system, was it originally designed and used for a bar/tavern? A mechanical engineer wants to know that a 2,700 square foot bar full of people will be comfortable with adequate fresh air when that tavern is full of people at maximum capacity. Sure - a twelve inch diameter fresh air intake (through the wall) could be tied into the return air duct for this existing HVAC unit. When this existing HVAC unit is interlocked with your deep fat fryer and associated heat exhaust vent, the make up air is sucked into the building and then either cooled or heated before replacing the greasy air and smoke from the fryer.


As already discussed, your exhaust system needs to be interlocked with the HVAC system (and associated fresh air intake).
Your CO and CO2 detectors need to be interlocked with the same HVAC system (and associated fresh air intake).
Determining whether-or-not the amount of fresh air intake will be adequate is typically the responsibility of the mechanical engineer.
I pray that you find an architect with his belly up to the bar so that you do not need to reach out too far to find one.

Welcome to the forum.

The HVAC system (which is really just a furnace) was not used for a bar/tavern before. There’s all sorts of problems with how it was installed, but luckily for me the building owner is taking cost of that along with the CO2 intake part for heating the space. However, the building owner doesn’t having them moving fast and inspector won’t issue my permits to build until it’s taken care of along with the kitchen exhaust and make up air.

So if I’m reading this correctly no matter what the exhaust make up air has to be tied in through HVAC? Or am I misunderstanding? It would be easier if allowed to tie the exhaust and make up together with a thermostat that has them both click on at same time. I appreciate all the help and understand the use of it is my discretion and and wouldn’t try to hold anybody accountable, it will just help me speed things up with mechanical contractor building owner hired.
 
To ensure that there is adequate clearance for both exhaust and vent, there are several options for how this is routed. But the number of elbows, diameter of the duct, and overall length of the duct, air velocity, and static pressure are all calculated together to ensure that you will be happy with the long-term performance and easy maintenance. And that is why the fees for a mechanical engineer are a justified expense. The HVAC contractor can sometimes do the math but they are biased towards making their job easier and selling you the materials that they already have inside their utility van. Sometimes the HVAC contractor and engineer work together to design something that works really well, easy to install, and does not cost too much.

No. The Make Up Air does not need to be tied to the main HVAC system. It is sometimes cheaper to do it that way but it may not be practical if the existing furnace and air conditioner are insufficient for a bar / tavern. Most of the projects that I work on, there is a separate kitchen exhaust fan and a separate make up air unit. These are typically located on the roof top and separated from each other by a distance of ten feet. These are not controlled by a thermostat but they do "click on at the same time". In other words, they are "interlocked". Most systems that I deal with are moving 2,000 cfm of air through the kitchen exhaust hood and an equal 2,000 cfm being sucked into the make up air unit. But if the fan for your fryer is only 400 cfm, then I do not understand why you make reference to 800 cfm or more. In any case, a small make up air unit with only 400 cfm or 800 cfm should be available for something around $1,000. That is certainly a lot less than the typical kitchen exhaust and make up air system for $30,000.

The only practical reason for having a thermostat is to ensure that the air flowing through the make up air unit is either cooled or heated before being introduced into the building. Again I say that the make up air unit does not turn on unless the exhaust fan is turned on.
 
I’m using a AutoFry machine and a Multichef Oven, along with a panini grill to do what I need.

You stated the AutoFry machine is exempt from the hood requirements because it has an integrated ansul system. But what about the MultiChef Oven and Panini grill? Are you sure they are also exempt from requiring a hood? They may not need a type 1 hood, but they may need a type 2 hood.

You also need to look into the energy code impacts on the exhaust / make up air. If your pulling out a lot of exhaust air you may be required to provide some sort of heat recovery on that exhaust air.
 
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