Akhand Ramayan Paath means singing/reciting the whole Ramyan without any break for continuously 24 hours. By performing this Paath one can have qualities of Lord Rama who is expert in removing hurdles and protecting the Family ethically.
The benefits of Akhand Ramayana are innumerable but few of them are:
It provides Peace, Prosperity & Happiness in the family.
It is considered auspicious for beginning of any new venture like starting of a Business, Entering a New House (Grah Pravesh), Birth of a Child, Marriage Ceremony, etc.
It prevents any unexpected harm and danger especially related to Health.
It creates a very pious and divine atmosphere at a place.
A good time to do this puja is Ram Navmi which is considered as the day of birth of Lord Rama.