A basement foundation is an architectural structure that basically secures a house or other building about a floor below ground level.The concrete floor in most basements is structurally not part of the foundation; only the basement walls are. If there are posts supporting a main floor beam to form a post and beam system, these posts typically go right through the basement floor to a footing underneath the basement floor.
Basement is a need of every house today, but according to Vastu basement should be avoided in residence because low room/space or empty space under the house is not considered auspicious
Adding a basement or finishing one is great for a low-cost, extra bedroom, family room, or workout room. Adding a basement also creates peace of mind for homeowners as it adds a safe space for you and your family in the event of inclement weather.