What type of roof is typically flat or nearly flat?

A flat roof is characterized by its minimal slope or a completely level surface, allowing for efficient water drainage when designed appropriately. This type of roof is common in commercial and industrial buildings, as well as in some residential designs, especially in urban areas where maximizing space is a priority. The flat design provides the opportunity to utilize the roof area for various purposes, such as rooftop gardens, terraces, or mechanical equipment.

In contrast, pitched roofs feature a significant slope that facilitates water runoff and snow shedding. Gambrel roofs, often seen in barns and similar structures, have a distinctive two-sided pitch, which is not flat. A butterfly roof resembles a V-shape, providing a central valley for water drainage, making it distinctly different from a flat roof structure. The key defining feature of a flat roof is its nearly horizontal plane, which aligns precisely with the answer provided.