Vent Pipe Sealing

[Red Rider]

FWIW: I simply follow the plumbing code (UPC) and used a 1 1/2" ABS vertical pipe extending through the roof. I sealed it as Melbo stated with the rubber to the exterior. I took it upon myself to screw a ABS tee ( painted to match the finish) and mounted it facing front to rear. 6000 miles this past summer and no problems.

[Scott & Heather]

Another vote for the "through the floor" vent pipe. Works great, one less leak potential on the roof...and no issues whatsoever.

[Brassman]

Not that it matters, but venting underneath is a violation of the NFPA 1192 RV code. At the very least people should know that there is a code--the enforcement is up to the guy doing the conversion. Personally, I don't care how someone vents their sewage tank. Just saying.

[luvrbus]

Out the bottom is not a vent just a overflow all seated coaches rest room equipped are power vented with a fan Prevost has a sealed SS tank with a vent fan and they stink lol  

good luck

[buddydawg]

I have had mine vented out the bottom for 3 years.  2 - 2" inch vents on opposite sides of the tank.  No issues so far. Just sayin..

Although I did leave provisions to vent through the roof if I find myself inclined.

[Bill 340]

Eagle 19952, of course we are suicidal and homicidal==  WERE BUS NUTS

[Lin]

Well, everyone knows that codes are merely handy suggestions.  This reminds me of a guy that wanted an easy way to connect his RV generator to his house in an emergency.  He made his own connection cord with male plugs on both sides.  He said it worked fine.  Nothing could go wrong with that, right?

To be honest, if I were building new, that vent would go out the roof.  However, depending on the complexity in a retrofit, I might cheat.

[Ed Hackenbruch]

I like to use Dicor Lap Sealant when i want to make sure something isn't going to leak. 

[thomasinnv]

I like to use Dicor Lap Sealant when i want to make sure something isn't going to leak. 

x2

[buswarrior]

Long ago, a busnut said they used the fitting that goes in the bottom of the kitchen sink as their roof sealing/penetrating device.

Doesn't stick up above the roof and hooks right up to regular plumbing fittings underneath.

Since we all enjoy leak free sink drains in our kitchens without another thought...
pretty neat idea?

happy coaching!
buswarrior

[Melbo]

I repair leaks under kitchen sinks every week.  A sink basket strainer assembly is not typically designed for a flexible install or any type of movement.

I would stick with something designed for a roof installation that is flexible.

BUT we are busnuts and we get a chance to do it anyway we want and then do it again and then do it again and -------------

Some things I have done LOTS and LOTS of times.

Just my way.

HTH

YMMV

Melbo

[Scott & Heather]

if I were to run it through the roof, I would use some sort of clamshell type fitting that squeezes on both the inside and outside of the roof and use eternabond double sided to seal it. I've used hundreds of dollars of the stuff...and it's amazing.