The structural differences between tower silos and bunker silos require different cover design, though many of the same materials can be used. Covers for tower silos need to match the shape of the tower itself as well as withstand the increased pressure from the weight of the silage, and their primary purpose is protecting the silage from rain and extreme cold. Weighting the silage cover is less of a problem in tower silos.
Materials for silage covers in bunker structures are more focused on their ability to withstand UV exposure and protection against physical damage such as tears or punctures. Since the flexible covers are weighted, they are forced to conform to the surface of the silage material and may be overlapped, so a custom fit isn't a key concern.
