As they taught me in RC grade school and HS, Catholic churches, the building IOW, has to be set aside for sacred use in a process called consecration. A bishop performs the consecration by anointing the building with holy chrism. What it does is remove the building from Satan's influence and makes it a place where God grants favors. But sometimes the RC church wants to use the building (or just room, sometimes) for secular reasons. Then it must do a decommissioning or secularization. The Church's Code of Canon Law says, “If a church cannot be used in any way for divine worship and there is no possibility of repairing it, the diocesan bishop can relegate it to profane but not sordid use.” (Whatever the word "sordid" means, in that sentence. A house of porn perhaps?) A church is then said to be desacralized. But until that moment, it is sacred. All the objects in it are, and any place you go to in it. Even eating areas. You can eat in a Catholic church, it is allowed. But you must never go number one or number two there. To soil anything that is sacred is considered a form of sacrilege. When they clean priestly garments, that is allowed. But they must channel the dirty laundry water out into a field, perhaps. Because then the laundry water is holy. It must not touch the water in the sewer, because that would profane it. I still remember when I was a kid. They used to have restrooms in Catholic churches. But that is forbidden in Catholic churches under Canon Law. (Unless you just want to wash your hands. Washing your hands to remove germs is OK. But are your hands also "soiled"?) If you really have to go, don't use the bathroom there. Hold it in until you go home. Or go to a gas station across the street. Or go outside (outside is not part of the sacrilized area) and go when no one is looking. Point your butt out the window if you have to. But don't soil that sacred commode or urinal. It is sacrilege.
Hmmm. One of the bible study classes I attend is in a Catholic Church, and I've used the restroom often. I've never heard of anyone mentioning this problem. There is of course a part of the building where the altar is situated: the Sanctuary. That is considered a sacred area. It's customary to genuflect before the altar, since the host (bread wafer) containing the sacred body of Christ is kept there. But I don't think the whole building is treated that way. In the Unitarian Church, where I also attend bible study with a group of atheists, the room where Sunday services are held is called the sanctuary and treated respectfully. We have our study services in a different room.
The main reason a lot of C. Churches here in Europe don’t have bathrooms is very banal - they predate modern plumbing and being sites of historic significance can’t have that many new interventions in the structure. Newer churches and other parts of even the older church complexes have them - monasteries, houses for parish priests, communal spaces etc. that routinely make part of the church complex. It would be mighty impractical to have priests, monks and nuns run out to public toilets on the first gas station every time they need to go As the previous post said you are not going to shit under the altar and will avoid it during mass (unless sick etc.), but otherwise it is not a thing.
I'm not sure. Everything else I said is true. How it applies to their bathrooms I don't know. But it probably does. Official Catholic doctrine plans for every little detail. As I said, they aren't even allowed to pour their dirtry laundry water down the drain.
I can't find anything about restrooms in Canon Law. PART III : SACRED PLACES AND TIMES TITLE I: SACRED PLACES (Cann. 1205 - 1243) CHAPTER I. CHURCHES
Roughly 90% of my country is catholic, I know more priests than I want to admit, part of my family is spending more time in the church (including sleeping in monasteries and pastoral centers in church complexes) than at home and I never heard of this either Btw what does "draining dirty water out in the field" even mean, plumbing has been around for a long time, and there are very few fields around cathedrals in multi-million overbuilt towns Also, every monastery has a church within it, and a lot of people live their regular lives. Does he think they go to the bathroom and wash their clothes somewhere else? I mean, you will not do it in the main body of the church, but that would not be technically possible anyway, there are no bathrooms under the altar any more than you have a toilet in the living room, bathrooms are adjacent to the main structure.
I think you're misinformed. What you say about bathrooms doesn't apply to the whole building called the church--only to the sanctuary. Obviously, it would be bad form to pee in the aisles or the pews, or to shit on the altar. Elsewhere in the building there are bathrooms.
Open drainage into a field would be against regulations in most western countries anyway, this whole topic is a bit bizarre.
It's called graywater drainage. (Sinks, washing machines, showers, etc.) Some states allow this. Blackwater contains human waste. In my state both are illegal unless processed to state standards.