The invention relates to a metering device for a washing facility, comprising at least one dispensing unit (4) for dispensing a chemical product to at least one washing bay (3) of the washing facility. According to the invention, for each dispensing unit (4), the device comprises at least as many chemical product pipes (6) as the number of washing bays (3) in the washing facility, and the metering device comprises a single chemical product force pump (7) for each dispensing unit (4).