rough plumbing

[bmac]

Hello All
I'm preparing to build a workshop and would like to rough in for future toilet/sink waste line. My question is this: Does line exiting building pass through or under slab footings?
I appreciate any advise.

[LazyPup]

Normally a building drain line will pass through the footer wall, however, when passing any pipe through a masonary wall you are required to sleeve it. To sleeve a pipe you first install a short length of PVC pipe at least two pipe diameters larger than the desired pipe and long enough to extend through the wall with 2 to 3 inches extending out each side. The desired pipe is then passed through the sleeve and the space between the outside of the desired pipe and the inside of the sleeve is filled with expandable foam.

[bmac]

Thank you for the reply. That's exactly the info I was looking for.

bmac

[LazyPup]

Bmac,,in my previous post i discussed the manner of passing a line through the masonary wall but i think my answer may have been a bit incomplete in regard to your question. The first consideration is the depth of the line. To determine the depth you have to measure from the location of the proposed watercloset (toilet) to the point in the foundation wall where the drain line will exit. Water closets require a 3 or 4 inch line so the required pitch is 1/8 of an inch per foot, which you can easily see is 1 inch for every 8ft of run. You have to allow an additional foot for the 90 ell and the closet flange. Once you compute the required pitch plus the foot you have to measure the depth of the sewer line you desire to tie into to see if you can maintain the desired pitch back to the watercloset. I have seen instances where building sat a great distance back from the street easment/public sewer or the septic tank inlet and once the required pitch was computed the structure floor actually had to be raised to meet the requirements.

[bmac]

I appreciate the added information. I will have to consider that. The workshop I will be building will be about 50 feet from my septic system. If I understand you correctly, the line will have to drop 6.5 inches. Hopefully the slab elevation will be sufficient.

bmac

[LazyPup]

Bmac. in addition to the forgoing information you also have to consider the frost line in your location. You said your estimated run was 50 feet so that is 50 x 50/8in = 6.25 in. you would also need an additional 1 foot for the 90 elbow under the flange as a bare minimum, however when you pass through the footer wall you have to be below frost line, so you would have to measure the run from the footer wall at frost line depth,(in my locality 36 inches therefore in this location the tank inlet would have to be a minimum of 36in/frost + 6.25in/required pitch + 42.25inches.) compute the pitch at 1/8 in/ft to the septic tank. The line inside the structure would then go from the footer wall penetration depth and backtrack to the toilet location again at a 1/8 in/ft rise in this case+ 1 foot vertical for the sanitary 90 up to the toilet flange. The virtical riser may be longer, that is just the minimum fitting allowance for the 90. You could still install the toilet if you do not have the proper elevations, but to do so, the toilet would have to empty into a lift station and the effluent would be pumped to the tank.