As an Architect, I've encountered all sorts of crazy bathroom layouts. Here are some of the worst ideas anyone has ever come up with:
1) Carpet on the floors. Seriously – I know of a famous architect who put carpet in the bathrooms of an Apartment. I know, because I lived there. It seems like a great idea – until the toilet overflows. Bathroom floors should be waterproof, non-slip, and easily cleaned. In-floor radiant heating systems can keep the floor nice and toasty in the winter. Acceptable materials range from sheet vinyl at the low end to Italian marble at the high end. The floor must be treated in such a way that it offers a high level of slip resistance, even when wet.
2) Bath mats. I've even been guilty of this bathroom mistake. Bath mats are hazardous because they can slip underfoot or trip people. They also never dry out fully, breeding dangerous bacteria and mold. They are impossible to vacuum too.
3) Toilets right next to bath tubs. Bad Fung Shui. Really smelly too.
4) Toilets right behind doors. Especially if the door swings into the toilet!
5) Bathrooms without windows or ventilation fans. Moisture accumulates from bathing activities and the bathroom never dries out. Did you want a bathroom or a mushroom farm? Excess moisture is the number one cause of mold. If air isn't ventilated to the outside, mold can spread through the entire house.
6) Tubs and showers without grab bars. Slipping in the shower or tub injuries over ¼ of a million Americans each year according to the New York Times 1
7) Toilets without grab bars. Are you seeing a trend here? People over 85 suffer half of all household injuries near the toilet. 1
8) Electric radiant wall heaters directly under towel racks. A fire waiting to happen.
9) Non GFI electrical outlet next to the sink, shower, or tub. Ground Fault Interrupter (GFI) outlets cut off the power to an appliance if they sense a short circuit. Imagine someone getting out of the shower wet and picking up a faulty hair dryer or electric razor. Newer building codes require GFI outlets, but older homes often have them.
10) Shower curtains. I've never seen one that didn't allow water to exit the shower and soak the bathroom floor. This is bad for two reasons – First it creates a safety hazard by making the floor slippery. Second, plolonged exposure to moisture is murder on floors and their supporting structures. It's an invitation for mold and dry rot. Tempered glass enclosures are generally worth the extra expense.
So there you have it! Avoid these bad remodeling moves and your new bathroom will be much safer. It will also be a more pleasant space for you and your friends and family.