Whether in the zone of positive or negative moment, an upstand beam is typically built as a rectangular beam. However, at the zones of negative moment, it is theoretically conceivable to construct it as an inverted T or L beam. In practice, however, this is not done because it is easier to produce a flat beam of sufficient size and strength than it is to produce a large-diameter beam with a small cross section. The main purpose of using an upstand beam instead of a straight beam is saving material while still providing the required level of stiffness. An upstand beam has two vertical posts at its ends, which reduces the amount of material needed by 25%. However, there are some disadvantages to using upstand beams: first, they are more difficult to cut accurately; second, they require more time to assemble because they must be bolted together; and third, they take up more space in the garage or shed. If you do choose to use upstand beams in your structure, make sure to buy multiple upstand beams from different manufacturers. Also, make sure their centers are aligned before being bolted together. Finally, check with your local building department to make sure you have all the necessary permits to build without violating any codes.