# Cutting into a load bearing cast iron stack



## pauliplumber (Feb 9, 2009)

Have any of you had to cut into a cast iron stack in a basement, when it leads to a first and or second floor bath and then through the roof of an old house? Obviously there is going to be a lot of weight, and you don't know how well it's supported in the walls if at all. If in the process of cutting a wye or cleanout in, the stack drops at all, big problem. Suggestions?


----------



## uaplumber (Jun 16, 2008)

Clamp on a riser clamp, support under it as needed with dunnage.


----------



## leak1 (Mar 25, 2009)

2by4 bracing and heavy bandiron.


----------



## Ron (Jun 12, 2008)

Yes clamp it in the attic, I did one a while back this was the only way to keep it from crashing back into the garage.


----------



## Plumberman (Jul 7, 2008)

Riser clamp is the way to go as Uaplumber said


----------



## 422 plumber (Jul 31, 2008)

If you cut in the basement, install a friction clamp parallel to and level with the bottom of the joists, then nail two 2x4's across the joists so the clamp is resting on them.


----------



## PipeDreamer (Mar 26, 2009)

Ron The Plumber said:


> Yes clamp it in the attic, I did one a while back this was the only way to keep it from crashing back into the garage.


Great idea


----------



## Plumberman (Jul 7, 2008)

Its code here to support vertical cast at every story, although I have yet to see any of them do that way.


----------



## ROCKSTARPLUMBER (Dec 14, 2008)

Riser clamp totaly. Sell them one on everyfloor. Tell them you noticed that the stack was not secured properly which could lead to bigger problems down the road.


----------



## Ron (Jun 12, 2008)

ROCKSTARPLUMBER said:


> Riser clamp totaly. Sell them one on everyfloor. Tell them you noticed that the stack was not secured properly which could lead to bigger problems down the road.


Thats the exact one I used.


----------



## Bill (Jun 17, 2008)

Ron The Plumber said:


> Thats the exact one I used.


same here.


----------



## Plumbworker (Oct 23, 2008)

those are industry standards...??


----------



## Plasticman (Oct 14, 2008)

good ole hanger iron, or plumbers strap most call it. Just wrap it around the pipe just below a joint in the pipe and nail to the stud on each side. Or, like Rockstar suggested, use a riser clamp.


----------



## pauliplumber (Feb 9, 2009)

Thanks for all the good advice. Put in friction clamp(s) and band iron where ever possible. I thought of using band iron but feared it might not be enough, but didn't think of the friction clamps.


----------



## SewerRatz (Apr 25, 2009)

Everyone we do we install a friction clamp in the attic and on the first floor. If you can not access it the soil pipe from the first floor then do it in the basement as suggested and nail in 2x4" for the friction clamp to rest on.


----------



## pauliplumber (Feb 9, 2009)

Good pic, thanks...


----------



## Herk (Jun 12, 2008)

It's always dangerous cutting that cast. There might easily be four or five hundred pounds of iron and rust hanging there. I have used band-iron, usually the heavier stuff, and wrapped it around the closet tee hub or something like that. You can even hang it in a couple of places to make it more secure.


----------

