Dreaming of big snake in house is a warning sign as per dream interpretation and meaning. The dream means that you have an enemy who is masquerading as friend. This particular person might cause serious problems in your family life.
The dream also means you will soon discover secrets about a family member or friends and it might cause trouble in your life.
Dream of big snake in house also means you need to solve small problems in life before they grow and become unsolvable.
For some reason you dream of big snake in house and you are happy means there will be destruction but this might help in improving things. It also means elimination of person or thing that was causing problems in your life.