I am considering taping into one of my cast iron stacks to add a drain. The cast iron is in very nice condition and has no problem. It runs into concrete on the bottom, the other side of the pipe has extensive plumbing connections attached to it, then it vents.

Would the best thing to do be to cut a foot or two out of the 4" pipe then add a PVC T with Fenco connectors? Is there a better way?

This is a vertical drop I am talking about. I understand that the horizontal is much harder to deal with.

Thank You
Jamie

Hello
I don`t see a problem provide the additional line is smaller and is sloped properly also be careful not to starve your vent with to many drain lines - you want to keep your main vent open - also make sure the vent is supported well before you cut and it could be a good time to add a clean out .
I find good anwers on Home Improvement - Do It Yourself - Home Remodeling | BobVila.com you may like to investigate more there

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Originally Posted by vexation

Hello
I don`t see a problem provide the additional line is smaller and is sloped properly also be careful not to starve your vent with to many drain lines - you want to keep your main vent open - also make sure the vent is supported well before you cut and it could be a good time to add a clean out .
I find good anwers on Home Improvement - Do It Yourself - Home Remodeling | BobVila.com you may like to investigate more there

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Thanks, I will do some more reading before I start cutting, but it sounds like it is the standard method.

The drains I would be tapping into it with would be 1.5 inch. It is a 4 inch vent and each fixture is connected to the venting system, can you have too many fixtures for a 4 inch drain line?

Jamie

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Originally Posted by jamiedolan

I am considering taping into one of my cast iron stacks to add a drain. The cast iron is in very nice condition and has no problem. It runs into concrete on the bottom, the other side of the pipe has extensive plumbing connections attached to it, then it vents.

Would the best thing to do be to cut a foot or two out of the 4" pipe then add in a PVC T with Fenco connectors? Is there a better way?

This is a vertical drop I am talking about. I understand that the horizontal is much harder to deal with.

Thank You
Jamie

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Hi Jamie,

To make a cut in a cast iron stack vent you will first need to support the pipe with a raiser clamp,(see image) so it doesn't come crashing down on you.
Support the raiser clamp with bumper jacks or 2 X 4's cut to size. You may make your cut using one of two methods. You may rent a set of ratchet cutters, (see image) not snap cutters. Or you could make your cuts with a Saws-All using metal blades. I would Install a 4 X 2 cast iron sanitary tee using No-Hub Bands,(see image) and convert to PVC from there using another No-Hub Band. You do realize that you will have to run a vent for your fixture don't you? You just can't connect a fixture to a stack that has fixtures draining fromn above without venting it first. You may run a vent out the roof or revent back into a existing dry vent. If local codes permit you may be able to get by with a AAV,(Air admittance Vent). Good luck, Tom

Good reminder Tom ! I agree with previous post: Support the old CI pipes otherwise it will break and fall down on your head !

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Originally Posted by speedball1

Hi Jamie,

To make a cut in a cast iron stack vent you will first need to support the pipe with a raiser clamp,(see image) so it doesn't come crashing down on you.
Support the raiser clamp with bumper jacks or 2 X 4's cut to size. You may make your cut using one of two methods. You may rent a set of ratchet cutters, (see image) not snap cutters. Or you could make your cuts with a Saws-All using metal blades. I would Install a 4 X 2 cast iron sanitary tee using No-Hub Bands,(see image) and convert to PVC from there using another No-Hub Band. You do realize that you will have to run a vent for your fixture don't you? You just can't connect a fixture to a stack that has fixtures draining fromn above without venting it first. You may run a vent out the roof or revent back into a existing dry vent. If local codes permit you may be able to get by with a AAV,(Air admittance Vent). Good luck, Tom

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The pipe starts at the ground, then goes up about 6 feet, then makes a 90 through a hole in a 8" thick concrete wall. So I am not sure it is providing very much support. At the moment I have some thing in the way of me getting a clear photo of that vent stack setup, but I will hopefully get that cleared out today and be able to show you what I mean.

As far as venting, I have a galvinized vent pipe 1.5 inch that runs almost directly above where this new sink will go. The galvinized is very stuck together, even though there is a union on it. I used several trick with 2 pipe wrenches and leverage and was unable to open the union or unscrew the pipe at the couplings. It is about a 30' run back to the soil stack for this vent pipe.

My plan was to cut out that oil pipe and to put in a new 1.5" PVC pipe to vent both the old sink and the new sink. Is there any reason this is a bad idea?

Thanks
Jamie

Hey Jaimie,

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My plan was to cut out that oil pipe and to put in a new 1.5" PVC pipe to vent both the old sink and the new sink. Is there any reason this is a bad idea?

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That's acceptable to replace toe old galvanized with PVC. You could cut out the old pipe and leave just enough stock to attach a 1 1/2" No-Hub band and convert toPVC.
I would still support the stack with a raiser clamp and supports. If you don't the entire weight will be on the joint of the 90 when you make the cut. . Also I would stll come out of the stack with a 4 X 2 cast iron sanitary tee and then convert to PVC.
Sound like a plan? Tom

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Originally Posted by speedball1

Hey Jaimie,

That's acceptable to replace toe old galvanized with PVC. You could cut out the old pipe and leave just enough stock to attach a 1 1/2" No-Hub band and convert toPVC.
I would still support the stack with a raiser clamp and supports. If you don't the entire weight will be on the joint of the 90 when you make the cut. . Also I would stll come out of the stack with a 4 X 2 cast iron sanitary tee and then convert to PVC.
Sound like a plan? Tom

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The only part I am confused on is that you say to use a 4x2 cast iron T, would I need to install this piece in the traditional method with packing / lead, etc.? then convert to the PVC above that with no hub connectors to fill in the space I had to cut out?

I can put a raiser clamp on the main part of the pipe in the basement and block it to the joists for support.

I will get some photos taken and uploaded later so I can make sure we are both understanding my situation correctly.

Thanks again,
Jamie

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The only part I am confused on is that you say to use a 4x2 cast iron T, would I need to install this piece in the traditional method with packing / lead, etc.? then convert to the PVC above that with no hub connectors to fill in the space I had to cut out?

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Sorry! I should have specified a N0-Hub Sanitary Tee. When you make your cut you will have two bald ends to connect with No-Hub Bands to the tee. I don't know how much pipe you plan on cutting out but I make my cut 1/4" over the total length of the san tee. You fill the space that you cut out with the fitting. Why would you replace the cast iron pipe with PVC? What am I missing here? Let me know. Tom

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Originally Posted by speedball1

Sorry! I should have specified a N0-Hub Sanitary Tee. When you make your cut you will have two bald ends to connect with No-Hub Bands to the tee. I dunno how much pipe you plan on cutting out but I make my cut 1/4" over the total length of the san tee. You fill the space that you cut out with the fitting. Why would you replace the cast iron pipe with PVC? What am I missing here? Let me know. tom

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I didn't realize that you could connect in a cast iron T with nohub connectors. I was thinking that a cast iron T would have hubs on it.

So I just want to get a straight cast iron 4"X2" that is hubless and 2 no hub connectors. And that extra 1/4" gap gets covered by the no-hub connector, correct?

Jamie

Good morning Jamie,
The gaskets in the N o-Hub Couplings will take up the extra 1/4" that I added to the cut. You will need (2) 4" No-Bands and (1) 2" Band plus a 4 X2" Cast Iron No-Hub Sanitary Tee. You do realize that you will have to run a vent for your fixture don't you? You just can't connect a fixture to a stack that has fixtures draining fromn above without venting it first. You may run a vent out the roof or revent back into a existing dry vent. If local codes permit you may be able to get by with a AAV,(Air admittance Vent). By the way, What fixture will you be picking up off the tee? Good luck, Tom

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Originally Posted by speedball1

Good morning Jamie,
The gaskets in the N o-Hub Couplings will take up the extra 1/4" that I added to the cut. You will need (2) 4" No-Bands and (1) 2" Band plus a 4 X2" Cast Iron No-Hub Sanitary Tee. You do realize that you will have to run a vent for your fixture don't you? You just can't connect a fixture to a stack that has fixtures draining fromn above without venting it first. You may run a vent out the roof or revent back into a existing dry vent. If local codes permit you may be able to get by with a AAV,(Air admittance Vent). By the way, What fixture will you be picking up off the tee? Good luck, Tom

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The T I am adding is for a small 2nd sink in the kitchen for the coffee area.

Thank You, I believe that I now understand how to make the drain pipe change.

I am going to take out a long run of cast iron drain waste vent that is about 1.5 -2" in size. It is the drain waste vent currently for the kitchen sink, and the laundry. I am going to add this new small sink to the save vent line.

I am planing on using 1.5" PVC for the vent, will this be OK? My only other concern is that the dishwasher is going to be in a new position and will be about 12 feet away from where it connects to the drain waste venting system. It's kind of in the middle of the room, so it isn't possible to run a standard vent pipe right to it. Do you think I should plan to use a AAV on the dishwasher. Will I be on running the 1.5" pvc for my drain waste vent setup?

Thanks
Jamie