The compactness characterizing the Cube-based Abode style (driven by the conflicting geometries of cube and sphere), as well as the layout rule-of-thumb of placing plumbing fixtures (especially those using hot water) close together, has causd me to rethink kitchen, bath, and utility rooms and how their spaces might be used more efficiently.
With regard to bathrooms, there are typically 2 full ones in the (vanishing) middle class American Dream Home, yet with a family of 4 for example, these 2 rooms with 3 fixtures apiece can be appropriated by half its members while excluding the other half from their needs at any particular given time.
To rectify this situation, it would seem that a single bathroom area could simultaneously serve at least 3 family members – depending on whether the semi-private vanity had 1 sink or 2. The fully private areas (with doors) would of course include the toilet room with the throne on one end and a hand sanitizer dispenser at the other.
The bath/shower room – also fully private – would generally be laid out such that the tub occupied one half, with the other half reserved for tub access, drying, dressing, a washing machine, and drier (if a solar drier proves inadequate or unfeasible).
Both this room and the lavatory would not require full headroom toward the back and thus could conceivably be nestled into the low wall area of the CBA home.
With the kitchen on the other hand, because it is in the realm of the open living area, the prospect of a relatively small one does not necessarily translate to a cramped space. A 4’+ x 4’+ floor area should be large enough to accommodate 2 people sharing prep, cooking, and dishwashing tasks while allowing a 3rd to come in an get a glass of water or something from the fridge. To effect such however, a “U”, “G”, or “L” shaped kitchen that wraps around that floor area would have to be well organized with a circular work flow. All would be anchored by the refrigerator, with whatever side the door opens on determining the flow direction. In the 75 sq ft kitchen example above, the door opens on the right for a clockwise flow. Immediately in that direction, counter space is alloted for groceries to be inserted or taken out quickly, and may also be used for prepping and dish washing. Next is a double sink and then more counter space for prepping. Continuing clockwise, the next function is the stove and then more counter space for plates and a one-stool bar.
In general the kitchen area should situate between the living and dining areas – with food storage placed at or near the abode’s polar side, and the bathroom should be on the sunnier south and west corner. Overarching these rules of thumb, the hot water heater should be placed at the center of hot water use, i.e., the compartmentalized bathroom on the kitchen side of that area. This heater in turn should be as near as possible to hot water panels on the roof. Of course trying to satisfy all these considerations can be a real challenge, but such is the balancing act of design, and the puzzle-solving fun.