I was in my attic doing some wiring and came across a 2" vent, I
accidentally touched it and it moved..."moved" as in slid down for
about two inches.
The 2" cast iron vent is original. I hired a plumber to do some work
on the bathroom below, and because the original vent line was in the
way of a new wall opening, he created a new 2" PVC vent line about 3
feet off the original cast iron vent line, then in the attic, he cut
the original cast iron pipe about 6 inches below the roof, then the 2"
PVC line turns towards the cast iron vent, and connected to it using a
no-hub coupling right above the turned up elbow.
So my bath is now all PVC, until it goes up to the vent and there is a
short piece about 6 to 8". That in itself is not a big deal...however
the fact that when I touched it it slid down is a problem. Once it
slid down, the up turn elbow is now lower than the other end, meaning
the almost horizontal run of that pipe in the attic is now sloping in
the wrong direction.
Not a problem, I just screwed in a piece of 2x4 between two ceiling
joists and some pipe straps and now it is sloping correctly.
However it makes me wonder, the fact that the pipe is sliding, I am
thinking it should have flashings and sealant against the pipe right?
does it mean the roof seal is broken? I have not gotten up on the
roof yet, I am a bit paranoid to climb up there. What is the proper
way to fix this? The second question is, since the pipe is sliding, I
assume if I were to loosen up the no hub coupling I should be able to
pull out the entire contraption on the roof? if so should I just glue
in a piece of PVC all the way instead of using a short 8" cast iron
A) yes and maybe (depends on what is there)
B) can't tell if it needs fixing even, from here
C) This is actually third (or fourth if count first compound query as
two instead of only one), but -- maybe but can't tell what's there from here
D) Could do that; whether it's better or simple depends on the
aforementioned what's there now.
IIRC you've got tile roof? If so, could be a pita.
If the present has a rubber boot that's still in good shape that it
moved a little may have had no significant impact. OTOH, if it is a
hooded exit, pushing it back up may have lifted the whole thing away
from the roof--probably not, but again w/o no info, no way to tell...
_Somebody'll_ (whether it's you or another) have to get up there and see
whatcha' gots and what it needs, if anything...or, of course, you could
simply wait 'til it rains next time and see if you have a leak and
assume if you don't it's ok... :)
If you do, you'll know for sure it isn't altho still won't help w/ the
specifics of what you need, of course...
You have two choices, 1) wait until the weather is better and reseal
the roof yourself, or (better), 2) have a pro come out and redo the
run in all PVC now. Obviously, it should have been done right the
first time, so consider hiring a more talented plumber. The $$
involved aren't worth fussing at the original plumber, but a rather
thorough inspection of his previous work for you would be wise.
The potential problem is that when the pipe came back up, how do you
know that nothing else pulled apart. Unless you can see all the
plumbing down to the drain line, you can't be sure that everything
pulled out to where it was before. And as others have said, who
knows what happened up at the roof. If you don't want to go onto the
roof to check it yourself, find a neighbor or pat someone. It will be
cheaper than repainting a ceiling if you develope a roof leak around
the vent opening.
I can see all the plumbing down to the drain line, nothing was
disturbed down below, the elbow when it turned from vertical to near
horizontal flexed, I think the cast iron pipe came loose when the
plumber cut the cast iron pipe or when he worked with it, and he
forgotten to tell me (or didn't want to).
Yes now I have to climb up to the roof to investigate. I hate the
The roof is not your enemy. The ground is. Make all roof to ground
transitions in a slow and controlled manner and you'll be fine.
Fear is natural, and you should have respect for heights. If heights
make you so uncomfortable that you start doing stupid things, knees
knocking and such, then hire someone to go up there.
If you support the cast iron there is no reason to replace the cast
iron going though the roof. If you go with PVC you will have to
protect the PVC from UV - painting works.
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