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[email protected][_2_] trader4@optonline.net[_2_] is offline
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Default Type B (B-vent) chimneys and HVAC contractors

On May 3, 3:44*pm, chaniarts wrote:
On 5/3/2012 12:28 PM, TomR wrote:





I have an ongoing chimney issue. *My existing 10-foot above-the-roof-line
masonry chimney has to come down because it is in bad shape. *I would like
to take it down to near the roof line (to maybe 1 or 2 feet above the roof
line), and then have the remaining masonry chimney relined and B-vent added
from the roof line up.


Someone suggested that I should try calling HVAC contractors and ask them to
just do the chimney relining etc. without changing or doing any work on my
heater. *What they would need to do is add a flexible metal liner inside my
existing masonry chimney, connect it to a metal double-wall "Type B"
("B-vent") chimney vent coming out of the top of the chimney, add a B-vent
cap on top of that, and point/repair the 2-foot masonry chimney above the
roof line.


Is this something that HVAC companies could or would do -- including getting
the permit for the work, etc?


probably depends upon where in the world you are, and how hungry they
are. we can't answer either.





I know that I can just call some HVAC companies and ask, but I thought that
I would check here first. *I never heard of HVAC companies doing this kind
of chimney work unless it was part of a job that involved repairing or
replacing a heater.


P.S. *The existing heater and hot water heater are gas-fired units, so Type
B ("B-vent") should be fine.


P.P.S. *I also have an ongoing issue regarding how high off the sloping roof
line the B-vent needs be according to code. *Some people are stating that
the rule is that the top of the B-vent needs to be at least 2 feet above the
point where the B-vent is horizontally 10 feet away from the sloping roof.
But, for natural gas appliances (which I have), when using Type B vent less
than 12 inches (mine would be 6 inch B-vent), then the 2006 International
Residential Code for one and two-family dwellings (mine is a one-family),
Section G2427.6.4 on Page 382 would apply.


Here is the link to the 2006 International Residential Code for one and two
family dwellings:
http://www2.iccsafe.org/states/newje.../PDFs/NJ_Res_C.....


Check out Page 382.


In my case, with a 12/12 slope, In think my B-vent would only have to go up
about 4 or 5 feet from the roof line.


Is that correct?


call your code inspector. again, we can't answer that. the permitting
agency is the only one who can.- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -


The latter question is the easiest. Just take some pics and
go over to the local code office. They will probably give you
the definitive answer. You can look at national codes all
day long and they are one source. But different places
are free to adopt or do what they want., Around here, NJ,
I've gone in to ask questions and they have been helpful.
Anything else is just speculation.