vent pipe

Fix'n it

i opened up a wall, and found this. 3 1/2" pvc and 4" iron(?). someone had fured out the wall to fit this. i want to make the pipe small enough to fit correctly. i am figuring that i can use 3" with no problem. and couple it to the cast iron that is through he roof, with supports to hold it (there are none now).

its just a vent. so would 3" cause any problems ?

there are 2 couplers (or whatever they are called. they are not fernco's)) above the top plate. then about 2' up to the roof. how would a guy get most of that pipe out, without damaging the roof ?

does that black pipe cut easy with a resip saw ?


thanx.

Attached Thumbnails

   

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

rjniles

Schedule 40 PVC DWV is not made in 3.5". I think you have 3" pipe in place. The OD of the pipe will measure about 3.5".

__________________
Location:
Coastal South Carolina

Fix'n it

ahh, they go by ID. ok then.

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

DannyT

can you take a photo of what's above the ceiling?
you can cut cast with a recip saw but you need a good blade and it takes a while. sometimes it depends on the cast iron, some of it is harder and thicker then others .

wkearney99

Cast iron like that is a ***** to cut with a saw. Rent a chain cutter. You wrap it around the pipe and the when you tighten the chain the wheeled teeth on it split the pipe pretty neatly. Ought to be somewhere nearby you can rent one. And if you're going to remove part of it you might as well consider what it would take to just remove all of it. Might as well get it out of the way now while you're in there, and double-check just how well the roof seal is doing at the same time.

Canucker

+1 on the chain cutter. Took out a house full of cast iron, well worth it. Makes a nice BANG when it snaps. haha

__________________
You can have it good, fast or cheap. Pick two.

Fix'n it

here ya go. can i separate them where the joints are ? i am sure it could be a problem getting them loose, age and all. but what are they joined with ?

Attached Thumbnails

 

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

Fix'n it

oh. i REALLY DON'T want to have to get on the roof. so idk about replacing the whole pipe.

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

Fix'n it

and what about the size of the new pipe ? i was doing some searching. and it was said that i could use 1/2 the size of the main. so if i use 2", that would be a lil more than 1/2 the size. and would fit in the wall just fine. and i am sure i could use fernco's ?

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

joecaption

Your going to have to get on the roof anyway you do it to change the roof jack since your going with a differant size pipe.

Fix'n it

joe. i was going to leave the top piece of pipe in, and couple to that. or, perhaps i could run the smaller piece through the older piece, then seal that above the roof , to the old piece ? i REALLY DON'T want to be messing with the roofing. it doesn't leak now, and i like it that way.

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

wkearney99

The joint could be just oakum (oiled rope) or it could be lead that was melted and poured in there.

If you're screwing around moving the pipe then you stand a good chance of causing the existing roof seal to change... and not for the better.

Run something inside of it? Why? Just use an adapter.

Fix'n it

adapter ? = fernco ?

__________________
DIY'er, out of necessity. if i did this for a living, i would make about $3.50 an hour
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

i didn't make this world. i just live in it.
be careful of whom you make fun of. one day, that could be you...

TheEplumber

Here's what you do-
Go rent the cutters mentioned earlier- get schooled in how to use it.
Buy a 3" shielded no-hub coupling and a 4x3 shielded no-hub coupling, 3" PVC/DWV pipe
Get a helper in the attic to hold the pipe going through the roof.
Now cut the pipe right above the first hub.
As the helper is holding the top piece, remove lower section of CI pipe- it will be heavy, replace with PVC/DWV pipe- use the couplings mentioned earlier.
Done deal -20 minutes

__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions

rjniles

Not sure why you want to remove the pipe, you can not go smaller than the 3" PVC that you have now. I know you want to not build out the wall but that is the best option.

__________________
Location:
Coastal South Carolina