Which of the following is NOT a characteristic of exposed structures?

The correct choice is that "Easy aesthetic enhancements" is not a characteristic of exposed structures. Exposed structures typically emphasize the raw materials and construction techniques, showcasing their unfinished or unrefined aspects. This usually involves using materials like concrete, masonry, or heavy timber in a way that highlights their natural beauty and structural functionality.

While aesthetic enhancements can be made to exposed structures, such as cleaning up surfaces or applying finishes, these enhancements often go against the initial design intent of maintaining an honest and raw expression of the materials. The fundamental characteristic of an exposed structure is to reveal the elements that are typically hidden or finished, rather than making them easier to enhance with decorative treatments.

In contrast, the use of masonry, concrete, and heavy timber is indeed characteristic of exposed structures. These materials are often chosen for their strength and aesthetic potential when displayed in their natural states. Masonry provides a robust appearance, while concrete can be left with a raw finish to highlight its texture and form. Heavy timber also is appreciated in exposed construction for its natural warmth and structural performance. Each of these materials contributes to the structural integrity and aesthetic appeal of the exposed design, reinforcing the notion that they are integral features rather than decorative enhancements.