Plumbing and Piping - Cast Iron and PVC connections
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hrdrok
08-25-04, 09:30 PM
I'm doing a bathroom remodel and have come across a few problems. The cast iron from the basement floor has been cut about 3 inches above the floor with a boot and PVC connection. The problem is the cast iron is not cut real straight across and the connection leaks. Can I put a 4 inch connection with a 3 inch end down into the sewer stack and put a boot on ? The also ran the PVC up to about a foot from the ceiling in the bathroom and put a boot on thier also. My question on this is how hard would it be to take the stack up thru the roof ? IM not sure if any straps are in the attic to hold the cast iron or it just sits on the floor and supports all the weight. Can I just take off the boots and pull the stack thru the roof or back down into the bathroom and run new ? How high does the stack have to be above the roof ? Any help would be great. Thank you in advance.
LazyPup
08-26-04, 08:53 AM
To answer your question about installing the 3 inch inside the 4 inch. The answer is simply NO. You my not reduce a waste line in the direction of flow.
If the stack in question is the main vent for the structure it is also required to run from the main drain up and through the roof undiminished in size.
Removing the existing cast iron stack could prove to be a very labor intensive job. Due to the weight of cast iron you would have to remove it in short lengths. that would require opening walls and working in the attic space.
I don't understand why you would want to remove the existing stack considering your probem is the joint at the base.
You stated that a portion of the stack had been removed and replaced with PVC coupled to the cast with rubber boots. In the trade the rubber boots are properly known as FERCO COUPLINGS and they are code approved above grade providing the proper FERNCO COUPLING is used. FERNCO couplings may not be used under slab.
FERNCO COUPLINGS are rated by the type of material they are made to fit, PVC, Iron Pipe (IP) cast iron pipe ( CI) etc. To couple PVC to cast iron you need a FERNCO PVC X CI coupling of the appropriate size.
To resolve your problem at the floor you will probably have to chip out the concrete until you get down to the next joint in the cast iron pipe. Although very heavy, cast iron pipe is also brittle so you should be able to break out the damaged part with a hammer. (Gloves and eye protection is highly recommended here) When you get to the next lower hub you should be able to break out the cast iron, then pry the lead and oakum out of the hub. ( I normally drill a few holes close together in the lead at one point to get a starting point, they use a 1/4 cold chisel to cut the lead. Once the lead is cut you should be able to pry it out fairly easy.
Clean the inside of the hub with a wire brush, then insert the end of a section of PVC into the hub and pack the joint with plumbers epoxy in the same manner as the origiinal lead was in the joint.
You are also required to install a cleanout at the base of the stack not less than 6 inches above the finished floor. The cleanout must be installed in a position that will insure a minimum of 24 inches access in front of the clean out.
To answer your question about how far through the roof a vent must extend.
It must terminate outdoors in free air, not less than 6 inches above the roof and not less than 12 inches hrozontal to any vertical surface. It must be a minimum of 2 feet above any building openings. It must be a minimum of 7 feet above any roof used as a deck, may not terminate under any vented soffit overhang and must be 10 feet horizontal from any window opening.
It must be connected to the roof with an approved flashing and may not be used to support flagpoles or antennas.
If the stack in question is the main vent for the structure it is also required to run from the main drain up and through the roof undiminished in size.
Removing the existing cast iron stack could prove to be a very labor intensive job. Due to the weight of cast iron you would have to remove it in short lengths. that would require opening walls and working in the attic space.
I don't understand why you would want to remove the existing stack considering your probem is the joint at the base.
You stated that a portion of the stack had been removed and replaced with PVC coupled to the cast with rubber boots. In the trade the rubber boots are properly known as FERCO COUPLINGS and they are code approved above grade providing the proper FERNCO COUPLING is used. FERNCO couplings may not be used under slab.
FERNCO COUPLINGS are rated by the type of material they are made to fit, PVC, Iron Pipe (IP) cast iron pipe ( CI) etc. To couple PVC to cast iron you need a FERNCO PVC X CI coupling of the appropriate size.
To resolve your problem at the floor you will probably have to chip out the concrete until you get down to the next joint in the cast iron pipe. Although very heavy, cast iron pipe is also brittle so you should be able to break out the damaged part with a hammer. (Gloves and eye protection is highly recommended here) When you get to the next lower hub you should be able to break out the cast iron, then pry the lead and oakum out of the hub. ( I normally drill a few holes close together in the lead at one point to get a starting point, they use a 1/4 cold chisel to cut the lead. Once the lead is cut you should be able to pry it out fairly easy.
Clean the inside of the hub with a wire brush, then insert the end of a section of PVC into the hub and pack the joint with plumbers epoxy in the same manner as the origiinal lead was in the joint.
You are also required to install a cleanout at the base of the stack not less than 6 inches above the finished floor. The cleanout must be installed in a position that will insure a minimum of 24 inches access in front of the clean out.
To answer your question about how far through the roof a vent must extend.
It must terminate outdoors in free air, not less than 6 inches above the roof and not less than 12 inches hrozontal to any vertical surface. It must be a minimum of 2 feet above any building openings. It must be a minimum of 7 feet above any roof used as a deck, may not terminate under any vented soffit overhang and must be 10 feet horizontal from any window opening.
It must be connected to the roof with an approved flashing and may not be used to support flagpoles or antennas.
hrdrok
08-26-04, 09:11 AM
The cast iron is still going thru the roof in about a 6 foot section. They put a boot on inside the bathroom wall and then ran PVC down to about 6 inches off the basement floor with another boot to the cast iron. The wall it runs in is down already so I can get to everything very well. How hard is it to replace the flashing on the roof ? I would just like to run the PVC from the basement floor up thru the bathroom and out the same roof hole. I know I will have to put up new flashing around stack. Is the cast iron pipe have a support on it in the attice area ? I was hoping to do this from the roof and in the house since I had just had new insulation blown in the attic and would hate to crush it down. I hope I have made my question more clear.