An adjustable roof jack comprising: a flange; a first cylinder having a first cylinder top portion being at an angle between 13 and 19 degrees and a first cylinder bottom portion, fixedly connected to the flange. There may be a second cylinder having a second cylinder top portion and a second cylinder bottom portion at an angle between 71 and 77 degrees. A second cylinder bottom fold is folded over a first cylinder fold to fixedly and rotationally connect at an angle between 13 and 19 degrees. A vent cap cylinder having a vent cap cylinder top portion and a vent cap cylinder bottom portion having at least one vent cap cylinder fold is folded over a second cylinder top fold to rotationally connect the vent cap cylinder to the second cylinder; and a vent cap assembly is fixedly attached to the vent cap cylinder top portion.
