Advice on new sanitation system construction

[DDW]

Peggy,I have ordered your new book, however I fear that it will not arrive in time and the old online one appears to be no longer online.I am having a new sailboat built and we are just in the process of constructing fiberglass holding tanks. There will be two, one for the forward head and one for the aft. The heads will be Lavac, as it appears to be one of very few that is designed not to leak.My questions are on inlets and outlets, including vents. Due to space constrains I intend to have only one inlet/outlet located at the bottom of the tank, and use plumbing to "Y" this into an inlet, outlet, and deck discharge. Is there any problem with doing this, other than the obvious: being the only discharge if something goes wrong in the plumbing (under the effluent waterline) you have to deal with it wet. There will of course need to be some diverter valves to make everything go they way it should, including sealing the other paths during pump-out from the deck.Second, is it possible or recommended to use PVC schedule 80 rigid plastic to accomplish any of the plumbing? Or is this material insufficiently impervious to odors? The advantage to me would be that everything can be more compact, compared to dealing with very stiff sanitation hose.Third, I intended to use a 1 inch vent line which I believe you recommend. However no one I can find makes a tank vent thru-hull fitting in 1 inch, so I would have to use a standard mushroom thru-hull. I am concerned about the possibility of insects or other critters entering the unscreened hose. Is this a problem? Also, the vents will need to be located well above the tanks in order to stay above the healed waterline. Given this limitation are there any basic rules to follow in routing etc.?Thanks in advance.

 

[Peggie Hall HeadMistress]

Email me...I'm in all the directories here

Even if you did have my book, no book can answer every possible question specific to every installation...and you have some unique issues. We need to talk. So If you'll email me, we can set up a time to do that.