new house - can I vent plumbing through false chimney

[gary]

Hi all, I am building a house (literally) and am doing the chimney this
weekend. Its a 2 story and the chimney is just for looks as my furnace will
vent out the side of the house. The roof is 8/12 and I would like to keep
the roof holes minimal. I am using ridge vents for venting so no holes
there. The bathrooms will be connected to the HRV vented out the side of
the house so no holes there. I am doing my own plumbing also. Can I run
all the plumbing vents into the attic and tie them altogether to one pipe
and use the chimney to vent one pipe to the outside?

If so how far out should I run the pipe? I was thinking about 4" as snow
will not be a problem here. Is there a problem if the pipe ends up higher
than the peak of the roof or would that be better/neutral? I haven't pulled
a plumbing permit yet, so I don't know what vent pipe size this final pipe
would need to be an/or expand to.

For information, the house has 1 master bedroom bathroom with tub& shower,
3 - 3 piece baths and 1 half bath for a total of 5 bathrooms. Kitchen with 2
sinks and basement bar area.

Thanks,
Gary

[jan]

Post by gary
Hi all, I am building a house (literally) and am doing the chimney this
weekend. Its a 2 story and the chimney is just for looks as my furnace
will vent out the side of the house. The roof is 8/12 and I would like to
keep the roof holes minimal. I am using ridge vents for venting so no
holes there. The bathrooms will be connected to the HRV vented out the
side of the house so no holes there. I am doing my own plumbing also.
Can I run all the plumbing vents into the attic and tie them altogether to
one pipe and use the chimney to vent one pipe to the outside?
If so how far out should I run the pipe? I was thinking about 4" as snow
will not be a problem here. Is there a problem if the pipe ends up higher
than the peak of the roof or would that be better/neutral?

Better. the wind will sucks out the smoke when the pipe runs higher then the
peak. so the smoke will sucked out of the chimney, thats better then that
the wind blows it into the livin'.
in holland we draw a line on 45degrees from the chimney to the peak, and
when the line dont cross the peak then the hight of the chimney is okay.

Post by gary
I haven't pulled a plumbing permit yet, so I don't know what vent pipe
size this final pipe would need to be an/or expand to.
For information, the house has 1 master bedroom bathroom with tub& shower,
3 - 3 piece baths and 1 half bath for a total of 5 bathrooms. Kitchen with
2 sinks and basement bar area.
Thanks,
Gary

[Verizon]

Post by gary
Can I run
all the plumbing vents into the attic and tie them altogether to one pipe
and use the chimney to vent one pipe to the outside?

Sounds feasible, but it would up to the local mechanical and plumbing
inspector. All depends on several factors, will need to talk to him and
probably detail exactly how the fake chimney is built and what all runs
through it.

You can combine all the vents in the roof cavity and continue out with only
one above roof termination (properly sized.) Older codes require a "main
vent" which is 3 In. all the way to the main drain; but the current practice
in the IRC is to base the vent size on 1/2 the reqd drain size. For the IRC
in combining vents for sizing, figure out what drain pipe would be needed to
serve the total {combined} drainage fixture load (DFU) and size the combined
vent at 1/2 that size. Usually a 1-1/2" vent will work in normal
situations, but may need to go up to 3 In. if frost closure is an issue.

The IRC also allows the use of what's called an "air admittance valve". This
is a small device mounted under the fixture that allows you to vent without
running a vent to outside air. Some states and locals don't allow it
because the plumbing unions have fought to keep it out (if you don't need to
run a vent out the roof, the homeowner can usually do the job himself and
doesn't need a licen$ed plumber.) Anyway, it's legal in most of the country
and can be used anywhere and everywhere in the system (system will still
need a stack vent to outside air to relieve positive pressures).

Post by gary
If so how far out should I run the pipe? I was thinking about 4" as snow
will not be a problem here. Is there a problem if the pipe ends up higher

This is always governed by local codes. Most common is 12 inches.

[gary]

Thx for the info. The air admittance valves are not code here. What I was
wondering - would I ever need to go to a 6" vent if I only had one vent for
the whole house through the "chimney"? What plumbers are doing here now is
where the vent goes up from inside it goes straight through the roof. The
average roof has at least 4 vents, one larger (4") and the rest smaller
about 2". Often they are popped through near the eaves as it runs up an
exterior wall. Plumbers don't take aesthetics into account with vents
running through the roof in the front of the house. A real pet peeve for
me......

Gary

Post by Verizon

Post by gary
Can I run
all the plumbing vents into the attic and tie them altogether to one pipe
and use the chimney to vent one pipe to the outside?

Sounds feasible, but it would up to the local mechanical and plumbing
inspector. All depends on several factors, will need to talk to him and
probably detail exactly how the fake chimney is built and what all runs
through it.
You can combine all the vents in the roof cavity and continue out with
only one above roof termination (properly sized.) Older codes require a
"main vent" which is 3 In. all the way to the main drain; but the current
practice in the IRC is to base the vent size on 1/2 the reqd drain size.
For the IRC in combining vents for sizing, figure out what drain pipe
would be needed to serve the total {combined} drainage fixture load (DFU)
and size the combined vent at 1/2 that size. Usually a 1-1/2" vent will
work in normal situations, but may need to go up to 3 In. if frost closure
is an issue.
The IRC also allows the use of what's called an "air admittance valve".
This is a small device mounted under the fixture that allows you to vent
without running a vent to outside air. Some states and locals don't allow
it because the plumbing unions have fought to keep it out (if you don't
need to run a vent out the roof, the homeowner can usually do the job
himself and doesn't need a licen$ed plumber.) Anyway, it's legal in most
of the country and can be used anywhere and everywhere in the system
(system will still need a stack vent to outside air to relieve positive
pressures).

Post by gary
If so how far out should I run the pipe? I was thinking about 4" as snow
will not be a problem here. Is there a problem if the pipe ends up higher

This is always governed by local codes. Most common is 12 inches.