[ebportman]

I am installing a bathroom in my basement. I opened the slab to connect my shower drain to the stub-out left by the builder under the slab. When I cut the stub out (3") it had about an inch of sewer sludge in it (damp, but not dripping wet). I have a septic tank. The my main waste stack transitions from horizontal to vertical about 6 feet up stream of the stub out, and then the main line exits my house about six feet after the stub out. I do not have a garbage disposal, and we never pour grease down the drain.

My questions:

1) Is it normal to have this type of sludge buildup in a newer home (only 3 yrs. Old)?

2) Is there anything I can do to clean it out short of calling a plumber, for example use some type of drain cleaner or a blow bag? I am planning to install a sink that will drain into a dwv fitting in the vertical portion of the main stack, so when I open it up I will have access.


Thanks in advance,
Eric

[speedball1]

1) Is it normal to have this type of sludge buildup in a newer home (only 3 yrs. Old)?

Depending on how many in your family you can build up a lot of gunk in three years. Soap has grease, washers discharge both grease and lint add the hair from tub/shower and lavatory and you have a lot of crap in your pipes.

Is there anything I can do to clean it out short of calling a plumber, for example use some type of drain cleaner or a blow bag?

As a repair plumber I have never recommended using harsh chemicals. In your drainage system. Besides they only seem to work in TV commercials and when you try to remove the water you could burn your hands or damage your eyes. Blow bags only work until there's a vent between the clog and the bag. Then all the pressure goes up the vent. The best way to clear a drain is to snake it out.

I am planning to install a sink that will drain into a dwv fitting in the vertical portion of the main stack, so when I open it up I will have access.

Your sink must be vented. How do you plan on venting it. With a AAV, a vent through the roof or a vent that's revented back into a dry vent?
Let me know, Tom

[ebportman]

Your sink must be vented. How do you plan on venting it. With a AAV, a vent through the roof or a vent that's revented back into a dry vent?
Let me know, Tom

I am venting my sink through the roof, inside my false chimney to the attic where I will tye into an existing vent stack, 2" vent.

My wife and I have 3 children, so there are 5 of us sending our wastes down the drain. I have to cut into the vertical portion of the main stack when I tie in my sink drain, so I am planning on also installing a cleanout so I can regularly snake/clean it.

Eric