tapping into 4" cast iron stack

[Ivan Vegvary]

Is there another way to tap a vent into a cast iron stack other than cutting out a chunk and installing a fitting? Last time I did this (over 20 years ago) the stack above the cut came down like a guillotine.
After all they do 'live taps' on high pressure water mains all the time. Vent is 1.5 inch abs. 4" c.i. stack is only 3 feet away. Presently the vent runs 22 feet horizontally before exiting the building then vertically up through the roof eave.
Thanks for any help.
Ivan Vegvary

[hrho...@sbcglobal.net]

Plumbers strap to support the pipe above the cut, and two sleeves, one at top and one at bottom of new pipe with the tap on the side. Only choices are the angle of the new incoming pipe. You can get a right angle input or one at perhaps 45 degrees downsloping (unless you put it in upside down)

[cl...@snyder.on.ca]

On Thu, 24 Oct 2013 16:59:38 -0700 (PDT), "hrho...@sbcglobal.net"
<hrho...@sbcglobal.net> wrote:

>Plumbers strap to support the pipe above the cut, and two sleeves, one at top and one at bottom of new pipe with the tap on the side. Only choices are the angle of the new incoming pipe. You can get a right angle input or one at perhaps 45 degrees downsloping (unless you put it in upside down)

Might be a good time to replace that CI stack with plastic - before
it rusts through and leaks. Getting hard to get insurance (new
policy) on a house with ci stack OR galvanized water piping.(here in
Ontario Canada)

[Retired plumber]

replying to Ivan Vegvary , Retired plumber wrote:

> ivanvegvary wrote:
> Is there another way to tap a vent into a cast iron stack other than
> cutting out a chunk and installing a fitting?

If it is a vent only, and not a drain, here is the easy way to do it:

Obtain a 4x1.5" abs saddle "Y" fitting. (A saddle fitting is sliced
lengthwise and clamped to an existing pipe. You can modify a normal 4x1.5.)

Drill several 1/4" holes (inside a 1" circle) in cast iron using masonary
bit.

Apply silicone or roofing sealer to fitting and clamp saddle fitting onto
cast iron, making sure the holes line up to the 1.5" opening. You need a
airtight seal to avoid potential sewer gas leakage.

Connect new vent.

Probably not up to code, but definitely will work.





--
posted from
http://www.homeownershub.com/maintenance/tapping-into-4-cast-iron-stack-767716-.htm
using HomeOwnersHub's Web, RSS and Social Media Interface
to home and garden related groups

[Ed Pawlowski]

There are fittings that clamp onto the pipe and you drill out a hole
with a hole saw. Check out saddle fittings

[Nate Nagel]

If you can find a "saddle tee" to fit, that will work as well e.g.

http://www.jumbomfg.com/product_cast_iron_and_brass_plumbing_specialties/saddle_fittings.htm

but keep in mind that you'll still have to drill a hole in the stack to
fit your pipe... doesn't sound like a fun job (but then again, neither
is cutting the pipe.) Different hazards though, I get nervous when
drilling anything larger than a 1/2" hole with a hand drill although
saws are safer than bits. Had my wrists wrenched/smashed too many
times, this is definitely a job for a drill motor with a T-handle.

If you do end up cutting, look into bracing the upper section of the
pipe with a riser clamp somehow before firing up the Sawzall or chain
cutter.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

[Caulki...@work.com]

On Thu, 24 Oct 2013 22:12:15 -0400, Ed Pawlowski <e...@snet.net> wrote:

>There are fittings that clamp onto the pipe and you drill out a hole
>with a hole saw. Check out saddle fittings

That must be a special hole saw blade. I doubt a common wood cutting
blade would handle the cast iron. I have used a angle grinder and just
cut a square, making 4 cuts, then use a saddle fitting.

[Ed Pawlowski]

Nothing special at all
https://www.ridgid.com/us/en/variable-pitch-hole-saws

[cl...@snyder.on.ca]

On Sat, 26 Oct 2013 04:30:02 -0500, Caulki...@work.com wrote:

Any bi-metal metal cutting hole saw will handle cast - or use a
carbide grit saw. The square hole works for a vent, but can cause
serious issues with a drain.