Installing a clean out at home
I’m having a slab and hookups put in my side yard for RV parking. The clean out will tap into the sewer system from my property in CA. I want to make sure the Contractor is doing it right, so asking...
Forum Discussion
I would use a 4" pipe with a 1/4" per foot slope and call it a cleanout.
Pipe dia. is normally dictated by the plumbing code and is based on the total number of "fixture units" in a residence connected to the pipe (sinks, toilets, bathrub, etc.). See this table for example. Largest no. of fixture units for a single fixture is for a toilet and a 3" dia. pipe is okay. Note that a toilet is 1.6 gal/flush. Plumbing fixtures normally have a P-trap and a vent pipe is required to prevent a trap from being sucked dry (and to prevent odors from coming out). A p-trap isn't really needed for an RV inlet and you won't need a vent pipe.
An RV dumps 30-ish gallons in a short period of time (way above a toilet at 1.6 gal/flush) and the code doesn't have a figure for RVs and could be why an inspector would just ignore it and consider it a cleanout. A 3" pipe could potentially be overwhelmed with the high flow rate/volume.
As for slope, the min. allowable is 1/8" per foot and 1/4" is what's usually used (excepting a vertical stack). Too little slope reduces the no. of allowable fixture units. Too much slope can result in the liquid and solids being separated and the solids being left behind in the pipe. I have a toilet in my workshop at home with a 3" pipe at 1/8" slope just under the slab. Couldn't get more slope but it works just fine.
Having said this, figuring out what to do isn't rocket science any anyone working as a plumber (and on permitted worksites) should have no problem deciding what's required. If hiring someone off CL who claims he/she's a plumber, you're opening yourself up to potential problems.
If you can't get a cleanout near where your RV will be parked, consider using a macerator pump.
Pipe dia. is normally dictated by the plumbing code and is based on the total number of "fixture units" in a residence connected to the pipe (sinks, toilets, bathrub, etc.). See this table for example. Largest no. of fixture units for a single fixture is for a toilet and a 3" dia. pipe is okay. Note that a toilet is 1.6 gal/flush. Plumbing fixtures normally have a P-trap and a vent pipe is required to prevent a trap from being sucked dry (and to prevent odors from coming out). A p-trap isn't really needed for an RV inlet and you won't need a vent pipe.
An RV dumps 30-ish gallons in a short period of time (way above a toilet at 1.6 gal/flush) and the code doesn't have a figure for RVs and could be why an inspector would just ignore it and consider it a cleanout. A 3" pipe could potentially be overwhelmed with the high flow rate/volume.
As for slope, the min. allowable is 1/8" per foot and 1/4" is what's usually used (excepting a vertical stack). Too little slope reduces the no. of allowable fixture units. Too much slope can result in the liquid and solids being separated and the solids being left behind in the pipe. I have a toilet in my workshop at home with a 3" pipe at 1/8" slope just under the slab. Couldn't get more slope but it works just fine.
Having said this, figuring out what to do isn't rocket science any anyone working as a plumber (and on permitted worksites) should have no problem deciding what's required. If hiring someone off CL who claims he/she's a plumber, you're opening yourself up to potential problems.
If you can't get a cleanout near where your RV will be parked, consider using a macerator pump.
