Not grouping water inlets
10 errors to avoid when designing your sustainable home plan layout: part 10
This entry is by far the less glamorous: pipes are noisy and expensive to repair. So make them short, accessible and far away from beds. A good trick is to stick kitchen and bathroom walls together and have a single inlet of water in between. That can be your technical space too, so while you're at it, make it accessible from outside. Place the bedroom toilet WC on a different wall than the bed, to avoid waking up in the middle of the night every time somebody flushes the toilet.