A system for mounting at least one solar panel on a building may include at least one panel mounting bracket including a base to be positioned on the building, a vertical extension having a proximal end coupled to the base and a distal end vertically spaced apart from the base, and a first lateral extension carried on an exterior surface of the vertical extension. The system may further include an adjustable height extension device for the at least one panel mounting bracket including a lower portion, an upper portion carried by the lower portion to be connected with the at least one solar panel, a second lateral extension carried by the upper portion and vertically aligned with the first lateral extension, and a height adjustment screw including a head carried by the upper portion to set a vertical height of the upper portion.