# 2" ABS vent pipe in garage fire wall



## Rio

We have a residential project that has a garage wall next to the addition.  We have 5/8" gyp. board on that common wall.  There is a washer and a dryer in the garage.   The contractor has run a 2" ABS vent through the fire wall into the attic above the addition, and apparently there is an ABS drainage pipe going through the fire wall also.  The inspector says this has to be metal.

Looking in the 2007 CBC (basically the same as the IBC), in Section 406.1.4, in part 2 it does say that "ducts penetrating the walls or ceilings separating the dwelling unit from the garage shall be constructed of a min. of 0.019-inch sheet metal" however the ABS is not a duct.  If we do need to have metal on it could we wrap the section of the ABS with a sleeve of the sheet metal?


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## mtlogcabin

Put a fire stop collar around it. Ask the inspector how can you meet the F & T ratings if you use metal?


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## beach

Typically, the plumbers around here (SOCAL) transition from ABS to cast iron pipe/fire caulk at the garage penetrations.....


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## Pcinspector1

Build a box around it, install 5/8" drywall, tape and mud?

Wait, better check with the home owner first!

pc1


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## Uncle Bob

Rio,

Not sure what codes you are looking at but;

A vent and/or drain is not a duct; it's part of the plumbing sanitary drain system.

Uncle Bob


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## Rio

Thanks for the good suggestion mtlogcabin and everyone else's response.  Could I impose on you again to elaborate on 'the F&T ratings'?

  Uncle Bob, I mentioned that the ABS is not a duct but it was the closest thing I could find relating to an object penetrating the fire wall mentioned in the IBC/CBC.  Any suggestions on where specific information is in the code book regarding drains penetrating fire walls?

Thanks again to all for getting back to me on this.


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## Kevin Turner

Rio,

Membrane penetrations IBC 712 talks about your F rating and steel, ferrous or copper pipes. It also says other listed materials and methods. Just put an Intumescent Fire Collar on it and it's a done deal.


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## mtlogcabin

F RATING. The time period that the through-penetration firestop system limits the spread of fire through the penetration when tested in accordance with ASTM E 814.

T RATING. The time period that the penetration firestop system, including the penetrating item, limits the maximum temperature rise to 325°F (163°C) above its initial temperature through the penetration on the nonfire side when tested in accordance with ASTM E 814.


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## beach

Like Kevin and MT said, put an intumescent fire collar on it and you're done, OR you can also just change out the penetrations to cast iron.


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## Rio

Thanks for the great information mtlogcabin and thanks to every one else for helping.  HAPPY THANKSGIVING!


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