Roofs with a pitch of less than 2/12 are considered flat, even though they technically have some slope. The minimum allowable slope for drainage is ¼” per foot. Steeper sloped roofs are generally more visually pleasing and tend to last longer, as the water runs off immediately and ice damming is avoided. https://civiljungle.com/pitched-roof/ beams and columns: The beam is a horizontal structural component that mainly carries vertical loads. In contrast, columns are vertical compression members that span from substructure to superstructure and have a vital role in transferring load from the top of the structure to the foundation. https://civiljungle.com/difference-between-beam-and-column/