# Sidewall B-vent termination



## Inspector 102 (Sep 12, 2013)

On many of the older homes in my jurisdiction, the water heater vent is extended through a sidewall and then turn upward for approximately 2 feet to a vent cap. These are normally 12" out from the exterior wall with stand off braces. Is this still an acceptable installation for a water heater replacement. Can't seem to find provisions in the code that address it. Thanks


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## north star (Sep 12, 2013)

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Which code are you using [ *RE:* Section G2427.3.2 in the `06 IRC ] ?

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## Gregg Harris (Sep 12, 2013)

Inspector 102 said:
			
		

> On many of the older homes in my jurisdiction, the water heater vent is extended through a sidewall and then turn upward for approximately 2 feet to a vent cap. These are normally 12" out from the exterior wall with stand off braces. Is this still an acceptable installation for a water heater replacement. Can't seem to find provisions in the code that address it. Thanks


You won't find it.

Take a look at IFGC 503.6.8 Exterior Wall Penatrations


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## ICE (Sep 12, 2013)

Okay by me.  What don't you like about it?I am picturing a 90 degree bend that code wouldn't allow.  But it was approved at one time and has worked well for a long time.  Unless the vent is being changed as well as the water heater, I would let it go.  I have seen just about every funky water heater vent imaginable and they all seem to work equally well.

View attachment 871


So inspector 102, I forgot to ask if your vent made it above the roof.
	

		
			
		

		
	

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## Gregg Harris (Sep 12, 2013)

ICE said:
			
		

> Okay by me.  What don't you like about it?I am picturing a 90 degree bend that code wouldn't allow.  But it was approved at one time and has worked well for a long time.  Unless the vent is being changed as well as the water heater, I would let it go.
> 
> I have seen just about every funky water heater vent imaginable and they all seem to work equally well.


 They may be working but "well" would be speculation. Unless the fossil fuel appliance is tested with a combustion analyzer when commissioned there is no way of knowing the fuel to air ratio and whether or not carbon monoxide is being produced. I would be willing to bet that 99% of all fossil fuel appliances have never been commissioned with an analyzer.

A huge misconception is that the gas pressure is set on the appliance at the factory and when installed there is no adjustment necessary.


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## MASSDRIVER (Sep 13, 2013)

Gregg Harris said:
			
		

> I would be willing to bet that 99% of all fossil fuel appliances have never been commissioned with an analyzer.


Thank the Lord Baby Jesus for that.

I wouldn't worry unless all the CO detectors in the blast radius were going off.

Brent.


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## Inspector 102 (Sep 13, 2013)

Still using the 2003 IRC in this area. The vent pipe extends out the exterior wall, then 90 degree upward with a vent cap approximately 2 feet above the elbow. The water heater was replaced and connected back to the existing vent which is probably 40 years old. Homeowner called and asked if these was code compliant and I explained that if no other changes were made, it could remain that way. They asked if code allows it and I am trying to find language that might specifically indicate that it is acceptable. Have not looked for installation instruction yet.


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## Gregg Harris (Sep 13, 2013)

Inspector 102 said:
			
		

> Still using the 2003 IRC in this area. The vent pipe extends out the exterior wall, then 90 degree upward with a vent cap approximately 2 feet above the elbow. The water heater was replaced and connected back to the existing vent which is probably 40 years old. Homeowner called and asked if these was code compliant and I explained that if no other changes were made, it could remain that way. They asked if code allows it and I am trying to find language that might specifically indicate that it is acceptable. Have not looked for installation instruction yet.


Has not been code compliant for at least 45 years according to NFPA 54 7.5.2 unless it terminates 2 feet above the roof.

7.5.2. e A vent extending through the exterior wall shall not terminate adjacent to the wall or bellow eaves or parapets,as provided in 7.14.1(direct vent) and 7.14.3( mechanical draft system)

Looking at a 1970 code book for WSSC in Maryland 203.76.8 Vertical Flues

Vertical flue pipes ( not connecting with any masonry chimney) on the exterior wall, shall be amply supported, properly flashed,insulated where required,dripped at the bottom,and provided with spacial cowl or ventilator at top if required. Material of construction not ordinarily required for appliance flues may be specified by the plumbing division in view of exposure.

I can not find anywhere  that specifically allows it to terminate near side wall or bellow the  roof line.


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## Span (Sep 17, 2013)

Maybe I were over regulate WH venting requirement. I thought gravity vent WH needs minimum 5' above vent hood.


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## ICE (Sep 17, 2013)

Span said:
			
		

> Maybe I were over regulate WH venting requirement. I thought gravity vent WH needs minimum 5' above vent hood.


5' is the rule.  Enough pipe is required to heat up and create a draft.
	

		
			
		

		
	

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I wouldn't say that we over-regulate water heater vent.  If anything, we under-enforce the regulations.  The majority of installs are done without permit.  I don't know of negative outcomes due to our lax performance.
	

		
			
		

		
	

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