Before buying a flat on the top floor of any building, do check up, whether the building’s overhead water storage tank is located over your chosen flat or not. If it is located right above your chosen flat, please do not buy that flat. If the overhead tank is located elsewhere, and not right above your chosen flat, you may buy that flat. The reason to avoid flats with overhead water tanks right over your flat, especially right over your bedroom, is that, water at a height is considered dangerous in Feng Shui and sleeping right under it, is considered risky.