A vertically-oriented structural building module configured for stacking with one or more other structural building modules of the same type, the structural building module comprising: a. a central core member aligned along a central core vertical axis, the core structure comprising an upper end, a lower end, and an outer surface; b. three or more upper structural arms each having lower and upper ends defining an upper arm length, the lower ends of the upper arms being fixably attached to the core outer surface in radially spaced relationship about the vertical axis, each upper arm extending outwardly and upwardly from the core its own vertical plane at a desired angle θ u relative to the horizontal; c. three or more lower structural arms each having lower and upper ends defining a lower arm length, the upper ends of the lower arms being fixably attached to the core outer surface in radially spaced relationship about the vertical axis, each lower arm extending outwardly and downwardly from the core at a desired angle θ d relative to the horizontal; d. upper tubular cans attached to the upper ends of the upper arms, the upper tubular cans each comprising an outer surface, an annular interior space oriented about a can axis and having an inner diameter, and upper and lower ends defining a can length, each of the upper tubular cans being attached to the upper arms in a substantially vertical orientation to align the annular interior space of each of the cans at a desired can angle θ c relative to horizontal; and e. lower tubular cans attached to the lower ends of the lower arms, the lower tubular cans each comprising an outer surface, an annular interior space oriented about a can axis and having an inner diameter, and upper and lower ends defining a can length, each of the lower tubular cans being attached to the lower arms in a substantially vertical orientation to align the annular interior space of each of the cans at a desired can angle θ c relative to horizontal; wherein each respective upper arm is aligned within the same vertical plane with a corresponding one of the respective lower arms to form an upper lower arm pair; wherein the upper and lower cans of each of the respective arm pairs is aligned about the same can axis to form an arm pair can axis; wherein the upper tubular cans are configured to be connected to lower tubular cans of one or more other structural building modules of the same type; and wherein the lower tubular cans are configured to be connected to upper tubular cans of one or more other structural building modules of the same type. a. a central core member aligned along a central core vertical axis, the core structure comprising an upper end, a lower end, and an outer surface; b. three or more upper structural arms each having lower and upper ends defining an upper arm length, the lower ends of the upper arms being fixably attached to the core outer surface in radially spaced relationship about the vertical axis, each upper arm extending outwardly and upwardly from the core its own vertical plane at a desired angle θ u relative to the horizontal; c. three or more lower structural arms each having lower and upper ends defining a lower arm length, the upper ends of the lower arms being fixably attached to the core outer surface in radially spaced relationship about the vertical axis, each lower arm extending outwardly and downwardly from the core at a desired angle θ d relative to the horizontal; d. upper tubular cans attached to the upper ends of the upper arms, the upper tubular cans each comprising an outer surface, an annular interior space oriented about a can axis and having an inner diameter, and upper and lower ends defining a can length, each of the upper tubular cans being attached to the upper arms in a substantially vertical orientation to align the annular interior space of each of the cans at a desired can angle θ c relative to horizontal; and e. lower tubular cans attached to the lower ends of the lower arms, the lower tubular cans each comprising an outer surface, an annular interior space oriented about a can axis and having an inner diameter, and upper and lower ends defining a can length, each of the lower tubular cans being attached to the lower arms in a substantially vertical orientation to align the annular interior space of each of the cans at a desired can angle θ c relative to horizontal;