STEP 3: Plumbing - sewage

Ok, plumbing was a whole new chapter for me - I will share what I learned, but remember by no means do I have the plumbing wisdom here - just this experience.  The only plumbing I created for the foundation was the drain pipes and vents for the sewage system. Since I will not be burying my dome and will have venting windows and doors in the structure, I did not provide for any extra vents in the foundation floor, something you would really want to think about when you berm or bury your structure.

Plumbing

I decided to have my water lines, electrical and propane enter the side of the dome, so they would be easily accessible for repair or changes, plus I didn't want the headache of figuring this out in the foundation - so it bought me time to focus on these aspects later.

In order to make sure I did my measurement correctly, I got my toilet (craigslist but new), bath and sink (VJ's in Rochester) and bathroom sink (a gift) ahead of time and placed them inside my future dome, making calculations for the thickness of the wall between the bathroom and the kitchen and shuffling thing around until I found their right spot. Then I decided how I wanted to connect these pipes. I decide to separate the gray water (sinks and bath) from the black water pipe (toilet) after it was informed this is the proper way to go, it also made sense to me for the future in case I wanted to separate these drains and their 'treatment'. The pipes for grey water I was told are 2" and the black water pipes generally 3", so I got those.

I was informed that the toilet also needs something called a toilet flange. Off course in order for the pipes to drain properly they need to be under a certain slope/angle. They rule of thumb that I got is at least 1/8" drop per 1 foot of pipe, or in other words approx 1" per 8 foot of pipe. Also, it is said not to make the drop too steep, since liquids will flow, but solids will drop and not flow with the liquids. If anyone had more info, please feel free to add to this knowledge!

Ok, another point that I find important to share is that the pipes need to be flush with the concrete floor once it is being poured, so use a level on a board (or if you got a laser even better) to make sure it is exactly that because if it sticks out you will have a hard time leveling the concrete floor around it and in case of the toilet and other drains like a shower or a bath that need to be connected at floor level, it is essential that they do not stick out above the concrete floor. Anyway, something else I remembered is that you can use duct tape to cover all the drains and an extra piece of carton board between the flange's moveable part and the concrete so it will not be stuck to the concrete and you will not be able to move the upper ring into the right position.

One more thing about the sewage pipes is that you need to use a coupler at the end of every pipe (flush with the floor) to make sure you can fit another pipe in there after the floor is poured to connect to say your sink. If you cut the pipe and make it flush with the concrete floor, you will have nothing to work with and build upon once the floor is done. Very important!!;) that would suck...