Abstract: In some aspects, deicer systems to distribute a deicing fluid along a roof of a building to limit ice dam formation can include: a pre-pressurized water source that provides pressurized water; a deicer solution source containing a deicer solution; a passive mixing system in fluid communication with the pre-pressurized water source and the deicer solution source, the passive mixing system being configured to combine the pressurized water and the deicer solution to form a deicer fluid; and one or more emitters configured to be disposed along the roof, the emitters being in fluid communication with the passive mixing system to receive the deicer fluid and dispense the deicer fluid along the roof. In addition, certain systems described herein can be run with an electric pump.