Squeaky floors were the best home security in 17th century Japan. You’d expect Japanese feudal lords to live in pristine houses with the sturdiest materials – and that is mostly true, save for their squeaky, creaky floors. Nightingale floors were flooring systems that “chirped” when somebody walked on it. They were installed in temples and palaces to alert of intruders. The floors were built in a way that the flooring nails rub against jackets or clamps, causing squeaking noises.