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Vents on Occupied Roof

duckbill

Bronze Member
Joined
Dec 8, 2009
Messages
51
Location
PA
2015 ICC Codes. The IPC Plumbing Code requires vents to terminate no less than 7' from a flat usable roof. Are there any such requirements for a kitchen hood exhaust termination?
 
Would be in imc

I am thinking maybe not that wording but some other code verbiage

Will look
 
Check word for word the code you are using

Depends on how you interpret this,

I don’t think I would want to smell Burger King, while setting on the roof

Imc

506.3.13


]outlets that terminate above the roof shall have the discharge opening located not less than 40 inches (1016 mm) above the roof surface

506.3.13.3


]outlets shall be located not less than 10 feet (3048 mm) horizontally from parts of the same or contiguous buildings, adjacent buildings and adjacent property lines and shall be located not less than 10 feet (3048 mm) above the adjoining grade level. Exhaust outlets shall be located not less than 10 feet (3048 mm) horizontally from or not less than 3 feet (914 mm) above air intake openings into any building.

Exception: Exhaust outlets shall terminate not less than 5 feet (1524 mm) horizontally from parts of the same or contiguous building, an adjacent building, adjacent property line and air intake openings into a building where air from the exhaust outletdischarges away from such locations.




 
Check word for word the code you are using

Depends on how you interpret this,

I don’t think I would want to smell Burger King, while setting on the roof

Imc

506.3.13


]outlets that terminate above the roof shall have the discharge opening located not less than 40 inches (1016 mm) above the roof surface

506.3.13.3


]outlets shall be located not less than 10 feet (3048 mm) horizontally from parts of the same or contiguous buildings, adjacent buildings and adjacent property lines and shall be located not less than 10 feet (3048 mm) above the adjoining grade level. Exhaust outlets shall be located not less than 10 feet (3048 mm) horizontally from or not less than 3 feet (914 mm) above air intake openings into any building.

Exception: Exhaust outlets shall terminate not less than 5 feet (1524 mm) horizontally from parts of the same or contiguous building, an adjacent building, adjacent property line and air intake openings into a building where air from the exhaust outletdischarges away from such locations.



Thanks CDA. The IMC seems quite concerned about horizontal separation but not so much vertical separation unless you stretch the meaning of adjoining grade level. From a safety standpoint (not really enforceable) I don't want someone looking face down into the exhaust fan. I may have to let the height go at 40 inches and ask for a railing.
 
Thanks CDA. The IMC seems quite concerned about horizontal separation but not so much vertical separation unless you stretch the meaning of adjoining grade level. From a safety standpoint (not really enforceable) I don't want someone looking face down into the exhaust fan. I may have to let the height go at 40 inches and ask for a railing.



I guess it would depend what all is on the usable roof

And what people are doing up there.
 
The project is a one-story shell building with two-story apartments at each end. There is a sliding glass door in the apartments that allows residents to walk onto and use the roof above the shell building. The roof top is a party place. Now a restaurant is moving into the vacant shell space. The plumbing code addresses this issue by requiring vents at 7'. The mechanical does not address this.
 
It's not that much of a stretch....
The discharge of the exhaust system must be
located to minimize accumulation of grease on parts
of the same, contiguous or adjacent buildings and to
prevent the entry of exhaust discharge into any fresh
air intake or other opening to any building. The
exhaust outlet must be located a minimum distance
above grade to protect passersby and to help the dispersion
of the exhaust into the atmosphere.
Exhaust
outlets must be a minimum of 10 feet (3048 mm) horizontally
from or 3 feet (914 mm) above any air
intakes which is consistent with other sections of the
code.

Tell the owner that he has a liability for blasting a drunken partier in the face with hot grease...Or slip and falls...
 
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Couple code sections come to mind.... (note that all are paraphrased sections)

501.3 Exhaust Discharge - The air removed by every mechanical exhaust system shall be discharged outdoors at a point where it will not cause a public nuisance and not less than the distances specified in Section 501.3.1. ...

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

506.3.13.3 Termination Location - Exhaust outlets shall be located not less than 10 feet (3048 mm) horizontally from parts of the same or contiguous buildings, adjacent buildings and adjacent property lines and shall be
located not less than 10 feet (3048 mm) above the adjoining grade level. Exhaust outlets shall be located not less than 10 feet (3048 mm) horizontally from or not less than 3 feet (914 mm) above air intake openings into any building.
Do note that adjoining grade is not a defined term; the roof deck, IMHO, would be considered the adjoining grade as it is an open area subject to foot traffic.
 
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Thanks Ty and "ouch", makes it difficult to meet in shared occupancies such as a nail salon in the ground floor of a 4 story condo next to onsite parking with a patio above.
 
This really isn't much different than discharging through an exterior wall per IMC 506.3.13.2 which says "discharge from such terminations do not create a public nuisance or a fire hazard." Similar to 501.3, public nuisance is difficult to define, and as long as the air discharge isn't directed onto something, a fire hazard isn't created, so the termination is permitted. That isn't going to stop the horrid smells from migrating into the park across the street, or the massive number of complaints from the park-goers once their tranquility has been compromised. This is where pollution control units come in. They are not required, but if installed they have regulations. Generally it's either common sense that drives the installation of these units or it's customer driven, whether from the park across the street or the owners of the condos that have access to the promised roof-top amenity. I would imaging that the plumbing vent would be relocated as well (even if it is installed 8' above the roof) once owners started using the roof-top amenity and have to endure the vent fumes being driven back at them during a mild breeze.
 
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