plumbing venting question

[StandUpGuy]

I think you should put the vent up through the roof ledge, like you're planning. End the vent a threaded fitting, like this:



Then make an extension pipe with a fitting like the one below, to thread into the tube sticking out of the ledge. When you are camped and raising the top, thread the extension pipe in to raise up the vent pipe.

I think you have a good idea in it. It is simply and clean. I could even try it at first with no extension to see if it works and then if it is a problem I could make the extension element.

[Wobbly Wheels]

I think vent stacks are one area where RV manufacturers have traditionally borrowed from residential rather than marine construction. Holding tanks up to around 100 gallons are vented with 5/8" hose and terminated with one of these vent fittings (Seadog p/n 352110, about $10 MSRP).


Using hose will allow it to flex as the top goes up and down, will still vent when the top is down, and will let you keep the fitting on the roof. Sani hose is a heavy, reinforced vinyl hose meant specifically to prevent holding tank odors from passing through it. Because it's so tough, it helps to warm it with a heat gun just before you tighten the hose clamps.
(Sealand p/n 345650, about $3/ft)

[StandUpGuy]

I think you should put the vent up through the roof ledge, like you're planning. End the vent a threaded fitting, like this:



Then make an extension pipe with a fitting like the one below, to thread into the tube sticking out of the ledge. When you are camped and raising the top, thread the extension pipe in to raise up the vent pipe.

This looks like a great solution. Simple. I think it will work fine.

[StandUpGuy]

As in the very awesome suggestion of jeprovo, I have made a threaded connection on my vent stack and fabricated a screw on extention of the vent stack for camping.

[StandUpGuy]

He is the stack with the extension removed and a vented cap in place for the road.