Plumbing a house boat

I am bidding on a project for a new houseboat build in Seattle. Anyone out there with experience doing this? Any potential pitfalls you can warn me about. I have done service work on houseboats but building one is a new animal for me.

I don't know how we can do underground drainage for the main floor. This barge is a concrete float filled with polyfoam. Can I dig that out to put in my pipes? I have worked on other houseboats that use a flexible waste connector, similar to what you would see on an RV but I don't know how I leave the boat. Do I core out the side wall? Sounds dangerous. Is a sewage ejector necessary? I hate to use one if not absolutely necessary.

Also the entire roof top is a deck. Where to put my DWV vents? Flagpole?

Looking at radiant floor for heating. Never done a heat loss calc for a boat. Any special tips?

Thanks,

PJ in Seattle

quote; Also the entire roof top is a deck. Where to put my DWV vents

You are in a whole new dimension and land based designs may not be appropriate or possible to install. Isn't there going to be a "structure" on top of the deck so it becomes a HOUSEboat?