A roof drainage system , comprising - at least two gutter brackets , each gutter bracket comprising - a back portion for attachment the gutter bracket to a building, - an intermediate portion extending outward form the back portion for receiving a gutter element , and - an outer portion extending from the intermediate portion , wherein - the outer portion comprises an adjustable adjustment member , comprising a flashing attachment means for receiving a flashing element , wherein - the height / vertical position of the flashing attachment means is arranged to be adjustable in an adjustment range (A) in relation to the intermediate portion - at least one gutter element arranged on said gutter brackets , and - at least one flashing element attached to the adjustment members of said gutter brackets , wherein - one of the gutter brackets is arranged higher than another of the gutter brackets so that a desired gutter slope diverging from horizontal level is provided, and - the adjustment members of said gutter brackets are adjusted such that said flashing element is in horizontal level, characterized in that the flashing element comprises -- a facade element and -- a base element arrangeable between the gutter brackets and the facade element , wherein - the base element comprises an attachment means for matching to said flashing attachment means of said at least two gutter brackets , and wherein - the facade element is attachable to the base element , and wherein the attachment means are arranged in at least one groove that extends in lengthwise direction on outer surface of the base element . - at least two gutter brackets , each gutter bracket comprising - a back portion for attachment the gutter bracket to a building, - an intermediate portion extending outward form the back portion for receiving a gutter element , and - an outer portion extending from the intermediate portion , wherein - the outer portion comprises an adjustable adjustment member , comprising a flashing attachment means for receiving a flashing element , wherein - the height / vertical position of the flashing attachment means is arranged to be adjustable in an adjustment range (A) in relation to the intermediate portion - at least one gutter element arranged on said gutter brackets , and - at least one flashing element attached to the adjustment members of said gutter brackets , wherein - one of the gutter brackets is arranged higher than another of the gutter brackets so that a desired gutter slope diverging from horizontal level is provided, and - the adjustment members of said gutter brackets are adjusted such that said flashing element is in horizontal level, characterized in that the flashing element comprises -- a facade element and -- a base element arrangeable between the gutter brackets and the facade element , wherein -- a facade element and -- a base element arrangeable between the gutter brackets and the facade element , wherein - the base element comprises an attachment means for matching to said flashing attachment means of said at least two gutter brackets , and wherein - the facade element is attachable to the base element , and wherein the attachment means are arranged in at least one groove that extends in lengthwise direction on outer surface of the base element . <EOS>