Attic Remodel-No Plumbing, Best Way to Add DWV

[David Seebeck]

I am adding two bathrooms upstairs in my attic. Anyone know best approach to add waste stack 3" to a 2nd floor where no waste line currently exists? All bathrooms plumbing is downstairs in three baths. Slab on Grade foundation. Two hot water heaters are upstairs in attic. No problem getting water. Regarding wasted line I have thought about going through one of the existing bathrooms by dropping the 3" line down the wall and tying into existing toilet waste line. I will have to cut up the concrete floor, patch together the pipes, etc. Sounds very messy. Also,I have thought about dropping a 3" line inside an exterior wall closest to where the main drain exists the house on it's way to the street. This will require cutting the side of the foundation to get pipe to the ground and patch into the main drain. Not sure about cutting the footing on a slab. I have seen where this technique is used and pipe penetrates exterior wall just above the slab and goes down into the ground. Not very pretty. My main drains exits at the front of the house. Any other thoughts would be welcome.

Thanks. Dave Seebeck

[Bob NH]

I have seen where this technique is used and pipe penetrates exterior wall just above the slab and goes down into the ground. Not very pretty. My main drains exits at the front of the house.

That's what I would do, and include some foundation plantings in the plumbing budget.

If they can make a cell tower look like a pine tree, then you should be able to comouflage and conceal a pipe with a yew.

[master plumber mark]

yes you can camoflage a drain pipe pretty easily
even in the front yard with a little immigantion...


what you got in mind I have seen done before,
just going down an outside closet and then instead of tearing up
the concrete floor, jsut going outside and digging down out in the ground
low m close to the slab....

I have seen poeple tie into the cleanout in the front yard too
and it didnt look too bad, if you got one, if you dont, then make one..

pine trees or other shrubs work pretty well

painting the pipe to match the house works too.

[dubldare]

Going 'outside' to tie in is not legal where I am. All building waste branches must tie-in prior to the building drain/building sewer transition.

Although here by code, the transition can occur within 2' of the foundation wall, it most always occurs within the building, rather than outside of it.

Point being, your connection should be on the house side of your last clean-out.

[hj]

How you make the connection to the main system is immaterial. Do it whichever way can be done the easiest and most aesthetically pleasing. But in most areas you cannot connect to a cleanout riser.

[David Seebeck]

If I drop my 3" stack down an exterior wall, cut the sole plate, notch the edge of the slab say 4" and stub out just below the brick it would allow the pipe to exit the building underground, albeit slightly underground. I will check code in Southlake, Texas regarding tieing in to main prior to exiting the building. If this is true I am back to cutting concrete slab and digging to expose the main. Yikes, trying to avoid this.

Thanks for all your help.

Dave

[David Seebeck]

Sorry I am a little slow in the AM. Anyway, what I meant to say, does anyone have experience notching the side of a concrete slab to allow for the stub out of the 3" sewer line below brick line. If I run into rebar can I simply cut through?

My city follows the 2003 international plumbing code. Does anyone know if this code allows for me to exit the building with the sewer line and tie in to the main line close to the house but on the outside versus inside?

Thanks. Sorry for the confusion.

[Bob NH]

"Anyway, what I meant to say, does anyone have experience notching the side of a concrete slab to allow for the stub out of the 3" sewer line below brick line. If I run into rebar can I simply cut through? "

Cutting any concrete structure will almost certainly result in generation of a big crack propagating from the place where it is cut. The crack will propagate into the floor and down to the bottom of the wall.

Foundations are designed to carry the load across areas that may not have equal carrying capacity. Weakening it can also cause deflections that propagate into the walls, breaking plaster or even drywall. If you have a tile floor it will break the tile. If it is carpet you might not notice it. You take your chances.

When concrete is poured, they put in little grooves so the cracks will not be random. Causing a crack by cutting the concrete is a lot like nipping a piece of paper to make it easy to tear, or notching a piece of wood to break it.

[David Seebeck]

I will contract with a licensed plumber to find the best way to tie into main line. This job is more than a diyer can handle. Thanks for all your input.

Dave