District Judge Vilas Bambarde convicted builder Sharad Bhai Mansingh Pawar and architect Anand Ashtaputre and sentenced them to three years in prison for the collapse of the "Sairaj" building in Wagle Estate here.
The five-storeyed building, constructed on a nullah using sub-standard construction material, caved in on November 7, 1998, killing 18 persons.
The police, at the time, had registered cases under relevant sections of the Indian Penal Code, including those dealing with causing death by negligence, against nine persons.
Lawyers Punit Mahimkar, Pravin Kulkarni and GB Chavan appeared for the accused.