rerouting 2" galvanized steel vent pipe

[NSB00]

I opened up a bathroom wall so that I could reroute a vent pipe that obstructs a cold air return channel.

There are 3 inputs to this pipe: 2" from toilet in this bathroom, 1-1/2" from basement laundry tub, 1-1/2" from basement bathroom sink rough-in (never installed).

My plan is to shorten the galvanized steel 2" vent pipe so that it can run horizontally within the soffit space rather than horizontally within the wall. The new horizontal pipe section will be PVC. The branches that connect to the vent pipe will be extended upward using PVC.

I understand that I will need to anchor the 2" vent pipe with riser clamps before cutting so that the pipe doesn't drop out of the roof. Since this bathroom is on the main floor and it's a 2-story house, one clamp will be added in the attic and one clamp will be added on the floor immediately above this bath.

I don't see any good easy way to cut the pipe to get a square cut. It's going to be a little awkward working in that space. I guess my best options are a reciprocating saw or a hacksaw with fresh blades and work slowly.

Any tips are welcome.

Thanks

 

[Terry]

A sawzall will make good work of it. Just make sure you have a new blade or two, and make sure the cut doesn't walk.
You might want to "marker" the line you are hoping to make first.
A Lennox 618 would be a good blade.

 

[Sponsor]

 

[Tom Sawyer]

That be some nice old school DWV there. Kinda brings a tear to my eyes to see it go.

 

[hj]

Pipes do NOT normally "obstruct" cold air returns. If the do anything they "get in the way" of warm air ducts.

 

[Tom Sawyer]

The new mechanical code won't allow dwv pipes in a cold air duct or chase anymore.

 

[NSB00]

Thanks for the tips. I will pick up a set of those blades for doing the cut with my Sawzall.

 

[hj]

quote; The new mechanical code won't allow dwv pipes in a cold air duct or chase anymore

That would make sense for plastic DWV piping, the same as for cabling, because of fire and toxic smoke, but NOT for metallic piping.