Cast iron sewer trap + pipe encased in concrete.

[SIWEL56AA]

Hello all, any help would be greatly appreciated.

I have come across a situation while attempting to replace my cast iron sewer house trap with PVC. The house trap is constantly backing up so after having roto-rooter come out and inspect, it has been determined that the house trap is closing due to corrosion... the hole is a little bigger than an old sliver dollar. The house is about 100 year old.

While digging out the trap I found the cast iron pipe encased in concrete along with the hubs on both end of the trap. My initial thought was to cut the cast iron pipe on the house side and then cut a piece on the sewer side and tie them in with 4" heav-duty stainless steel no hub couplings, without having to replace the entire pipe on both sides of the trap.

My question: is there some type of chemical that can dissolve the concrete from around the hub and or a way to remove the concrete from the hub/ pipe?

Pic is attached

Thanks for any advice on this matter....

Siwel

 

[Breplum]

House traps are leftover garbage idea long since abandoned. You do not need a house trap.

 

[Sponsor]

 

[Jeff H Young]

Dont think pouring acid down is going to help. We dont really use house traps here Id be eliminating it as well. however If I was in some other state back east since Ive never even been to those places I guess I might check with building department. I dont know if I ever seen a house trap here

 

[Jadziedzic]

Search the 'net for "concrete dissolver" and you'll find a number of different brands out there; no personal experience with their use.

 

[Reach4]

If the local codes permit, remove the whole-house trap. I hope that is open to you.

If the local code is one of the few that still requires that, you can get those in plastic and cast iron. If the deposits inside are not mechanically removable, it would probably be better to replace than try to dissolve deposits chemically.

It is not totally clear if you are looking to dissolve perceived concrete inside of the pipe, or the concrete around the pipe. I presumed outside. If there is too much concrete to break away, consider going around the concrete.

 

[SIWEL56AA]

House traps are leftover garbage idea long since abandoned. You do not need a house trap.

Thank you for your reply, however house traps are required in my state/ municipality of New Jersey.

 

[SIWEL56AA]

Search the 'net for "concrete dissolver" and you'll find a number of different brands out there; no personal experience with their use.

Thank you. I found something that might work. I'll keep you all posted on its results.

 

[SIWEL56AA]

If the local codes permit, remove the whole-house trap. I hope that is open to you.

If the local code is one of the few that still requires that, you can get those in plastic and cast iron. If the deposits inside are not mechanically removable, it would probably be better to replace than try to dissolve deposits chemically.

It is not totally clear if you are looking to dissolve perceived concrete inside of the pipe, or the concrete around the pipe. I presumed outside. If there is too much concrete to break away, consider going around the concrete.

thanks for your reply. I'm looking to remove concrete around the outside perimeter of the 4 in CI. The pipe for 100 year old in good condition, I just need to remove enough concrete to be able to connect a coupling.

 

[DIYorBust]

I never knew that house traps were considered dispensible. Can you explain the logic?

 

[Reach4]

I never knew that house traps were considered dispensible. Can you explain the logic?

https://terrylove.com/forums/index.php?threads/house-trap.804/

I think the reason to have them was to inhibit rats.

The reasons to not have them is the houses vent the sewer main, they are clog points themselves, and they make it harder to rod out the house sewer pipes.

 

[PlumbumZepplin]

Wouldn't they have to be vented like any other trap to actually be effective? Are they vented that way where they are required?

 

[Reach4]

Wouldn't they have to be vented like any other trap to actually be effective? Are they vented that way where they are required?

Yes, good point.

Sometimes they show a vent on the house side, and sometimes on the city side.

 

[Sylvan]

House traps are leftover garbage idea long since abandoned. You do not need a house trap.

House traps are still required in a civilized area because UNLIKE those who say it is "garbage" they never encountered a floor drain in a boiler room that did not have its trap replenished allowing flammable sewer fumes from entering the structure and causing an explosion

Today many lax areas allow "cheater vents" which depend on a piece of rubber to prevent carcinogenic fumes from entering a structure. The House trap on a sanitary system helps prevent this from happening

Many times in older buildings there is a toilet or other fixture that has not been used in months the trap seal has long ago evaporated and the house trap just adds a little more protection from the unknowing

Personally, I would replace as much as possible

RE Vent on the street side of the trap

On the "city side" would not help the vent terminal to remove foul air. It would allow the city sewer system to vent outside of the building causing a rancid smell

Normally a FAI is installed within 4 feet of the building house trap.

As air enters the FAI being cooler than the air in the system warmer air rises as witnessed by hoarfrost during the colder weather

 

[Sylvan]

Yes, good point.

Sometimes they show a vent on the house side, and sometimes on the city side.

On the "city side" would not help the vent terminal to remove foul air. It would allow the city sewer system to vent outside of the building causing a rancid smell

Normally a FAI is installed within 4 feet of the building house trap.

As air enters the FAI being cooler than the air in the system warmer air rises as witnessed by hoarfrost during the colder weather

 

[Jeff H Young]

Are house traps required throughout your states or just certain urban areas? and current code still require all connections to public sewer be trapped? I kind of figured the code was old and outdated but in dense populated places might require the trap even today because potential loss could be much greater in a big city as compared to suburban or small town

 

[Sylvan]

Are house traps required throughout your states or just certain urban areas? and current code still require all connections to public sewer be trapped? I kind of figured the code was old and outdated but in dense populated places might require the trap even today because potential loss could be much greater in a big city as compared to suburban or small town

I would think a residential building 27 stories high as well as the more common size apartment buildings and even 1 and 2 family homes should have a house trap when connected to the public system

Too many people hire handymen who have no idea why there should be a vent and when they install a cheater vent inside a wall with no access then the problems arise when they do the bathroom alterations or the kitchen and the cheater vent fail or even worse they install a blind vent

Without a house trap, the city sewer fumes are not prevented from entering a building path of least resistance.

The house sewer line is pitched down to the city sewer and a vent line is pitched up from the point of disposal

Therefore the main house sewer acts as a vent for the city sewer system and with no house trap the fumes enter the building and escape through the vent terminal as long as the vent piping inside the structure has no defects

So when someone says "You do not need a house trap." you have to question their wisdom as you have a lot to lose by not installing one considering all the traps in a home that are not replenished

People in areas prone to drought may have a combination of waste and storm system so the storm traps will be lacking a trap seal and the sewer fumes will escape though the floor and yard drains

With the low flow fixtures in older buildings that once had 3.6 or more GPF are now using 1.6 and 1.3 toilets and the main lines are not being scoured as originally designed and the sewer fumes contain hydrochloric acid which causes the top of the sewer lines to split open

If there is a fixture trap that lost its seal or vent pipe that is corroded the fumes are not prevented from leaking inside the walls going unnoticed

Adding a house trap is just adding another means of protection


We replaced over 250 feet of 5" XH CI that split in a crawl space because someone doing an alteration decided to remove the house trap

 

[Sylvan]

Poor venting because no house trap

 

[Sylvan]

No house trap sewer fumes entered from the street sewer causing the piping to split on top.

“When cast iron waste pipes fail, it's usually due to corrosion from within. As a result of what runs through waste lines, hydrogen sulfide gas can form. This can oxidize and produce sulfuric acid, which corrodes cast iron"

Installing a house trap would have prevented this as the trap would stop sewer gases from entering this waste line

It only took 10 years to destroy 100-year-old piping

 

[Sylvan]

House traps are leftover garbage idea long since abandoned. You do not need a house trap.

Just look at the pictures above and explain why installing a house trap is a "garbage idea"???

 

[SIWEL56AA]

Hello all, any help would be greatly appreciated.

I have come across a situation while attempting to replace my cast iron sewer house trap with PVC. The house trap is constantly backing up so after having roto-rooter come out and inspect, it has been determined that the house trap is closing due to corrosion... the hole is a little bigger than an old sliver dollar. The house is about 100 year old.

While digging out the trap I found the cast iron pipe encased in concrete along with the hubs on both end of the trap. My initial thought was to cut the cast iron pipe on the house side and then cut a piece on the sewer side and tie them in with 4" heav-duty stainless steel no hub couplings, without having to replace the entire pipe on both sides of the trap.

My question: is there some type of chemical that can dissolve the concrete from around the hub and or a way to remove the concrete from the hub/ pipe?

Pic is attached

Thanks for any advice on this matter....

Siwel