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Vent terminal location

Sifu

SAWHORSE
Joined
Sep 3, 2011
Messages
2,813
Let it be known that I am not currently a plumbing inspector, haven't been one for nearly three years and don't have an adopted plumbing code to enforce even if I wanted to. That said I found a home with the vent terminals extended to the roof deck openings where the roof vents (turbines) were installed. This was for every vent. The owner said he wanted to avoid excess roof penetrations. My first instinct was to turn it down but ....not a plumbing inspection. Not sure if a building inspection failure existed yet or not but I got to thinking, is it a flat out plumbing defficiency? Codes require the vent to be terminated (insert #) inches above roof. Since the turbine does this would that be considered? Codes require it not be located beneath an air intake, would an attic turbine be considered an air intake? (I figure yes if conditions are right). I think it is a very bad installation and told them so but that I had no enforcement capabilities so that had no teeth. BTW the rest of the plumbing was even worse. Any other ways this would have violated the code?
 
2009 IPC

903.3 Vent termination.

Vent stacks or stack vents shall terminate outdoors to the open air or to a stack-type air admittance valve in accordance with Section 917.

2009 IRC

P3103.1 Roof extension.

Open vent pipes that extend through a roof shall be terminated at least 6 inches (152 mm) above the roof or 6 inches (152 mm) above the anticipated snow accumulation, whichever is greater, except that where a roof is to be used for any purpose other than weather protection, the vent extension shall be run at least 7 feet (2134 mm) above the roof.

P3103.2 Frost closure.

Where the 97.5-percent value for outside design temperature is 0°F (-18°C) or less, every vent extension through a roof or wall shall be a minimum of 3 inches (76 mm) in diameter. Any increase in the size of the vent shall be made inside the structure a minimum of 1 foot (305 mm) below the roof or inside the wall.

P3103.3 Flashings and sealing.

The juncture of each vent pipe with the roof line shall be made water tight by an approved flashing. Vent extensions in walls and soffits shall be made weather tight by caulking.

Turbine vents seize up all the time. Bad termination idea
 
Also, P3103.5 - Location of vent terminal.

An open vent terminal from a drainage system shall not be located less than 4 feet

(1219 mm) directly beneath any door, openable window, or other air intake opening

of the building or of an adjacent building, nor shall any such vent terminal be within

10 feet (3048 mm) horizontally of such an opening unless it is at least 2 feet

(610 mm) above the top of such opening.

Your wind turbines could allow air intake in to the attic space.

Also, P3114.7 - Vent required.

Within each plumbing system, a minimum of one stack vent or a vent stack shall

extend outdoors to the open air.

Also, P2503.1 - Inspection required.

New plumbing work and parts of existing systems affected by new work or

alterations shall be inspected by the building official to ensure compliance with

the requirements of his code.



Also, P2503.2 - Concealment.

A plumbing or drainage system, or part thereof, shall not be covered,

concealed or put into use until it has been tested, inspected and approved

by the building official.

As long as we're searching for applicable code sections, might as well

"pile it on!" :devil



.
 
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My question - Are the turbines being used as an attic ventilation requirement? If so, IMHO, it would be more than just a plumbing issue, it would also deal with a building/energy code issue. Energy and building codes deal with the minimum opening size for upper and lower attic vents. Add a plumbing vent and do you still have enough attic ventilation?
 
Alias said:
My question - Are the turbines being used as an attic ventilation requirement? If so, IMHO, it would be more than just a plumbing issue, it would also deal with a building/energy code issue. Energy and building codes deal with the minimum opening size for upper and lower attic vents. Add a plumbing vent and do you still have enough attic ventilation?
Got side tracked but that was kind of what I was going to day. It could void the warranty on the shingles if the openning size for the ventilation is compromised.
 
It would be a stretch to say the vents cut down the available area of ventilation within the turbine since the vents barely extend to the plane of the roof. As for the required ventilation I am pretty sure they are OK with the amount of ventilation. I am not allowed to enforce the plumbing code so while all the references are valid I can't use them for anything other than as information. So I will tell them they may have a stinky, potentially methane filled attic at times and when they call a pro to come fix their problems to make sure to tell him the "not" plumbing inspector told them what was going to happen.
 
The roof turbine vents are exhausters, not intake, however this installation is not much different IMO if the vent terminated into a ridge vent; roof cap vent or at a gable vent. It may be looked at as thru the roof or above the roof line but it would not be outdoors to the open air.

3104.1 Connection.




All individual branch and circuit vents shall connect to a vent stack, stack vent or extend to the open air.



ps. if he didn't want to make any more penetrations then necessary he could have use a different type of roof vent!



Francis



 
Attic vents are never an option. You're talking about sewer gas. It goes outside. An attic vent isn't outside. Ok so some will argue, "Oh no, I can make it work." So what. It is still a code violation for a damn good reason.
 
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The purpose of plumbing vent is to maintain neutral pressure on the system. From a webpage:

"A 12 inches turbine roof vent which has a constant wind flow rate of 5 miles-per-hour can simply remove 347 cubic ft of air for every minute out of your attic. A single 14 inch turbine vent getting a 15 mph winds can release around 1, 342 cfm of humid air". Constant negative pressure on vent system may allow trap siphon.
 
We now have a separate HVAC inspection from a state inspector. Until last year, we did HVAC inspections at the same time as a building insp. I still found HVAC violations after that change and our CBO told me that I was the "building inspector". Which he means the "entire" building.
 
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