In my plumbing system design, both the first and second floors have a set of toilets, including separate facilities for men and women. These are designed back-to-back, sharing a common pipe system. Both the men's and women's toilets have two sinks each. The men's toilet has two sitting toilets and one urinal, while the women's toilet has three sitting toilets.
In my plumbing design, I have included common hot and cold water, as well as a sanitary pipes. Additionally, I've integrated a rainwater collection system, taking advantage of the frequent rainfall in Copenhagen and the presence of two patios. The water from the central patio's pool is directed to a Mechanical Room for processing, then used for flushing toilets. This forms another pipeline in your system, enabling you to save water resources for toilet flushing.
Since the bathrooms on both floors of your building are stacked and aligned, the design didn't pose too many troubles. However, a challenge arose because I've set up only one wall, serving as the partition between the men's and women's bathrooms. This meant I could only install one pipe system to be shared by both sides. When connecting the pipeline to the fixtures, manual adjustments and connections might be necessary, which can be a bit tricky.
