A gas separation module includes at least one inlet port, a plurality of outlet ports, and a plurality of hollow fiber membranes. Individual fibers have a feed end and a product end with a retentate interior side and a permeate exterior side. The module includes a feed tubesheet within the shell segregating the at least one inlet port and the permeate side of the fibers. The feed tubesheet includes a matrix and at least one segment joint. The segment joint separates segments of the feed tubesheet from one another. A formation method includes positioning a hollow fiber membrane material in association with at least one tubesheet segment joint and applying a matrix. The method includes forming a feed tubesheet from cured matrix and the segment joint and forming a plurality of hollow fiber membranes from the fiber material. The segment joint separates segments of the feed tubesheet from one another.