What is the term used to describe constructions that impede heat flow or water distribution significantly?

The term that describes constructions that significantly impede heat flow or water distribution is "obstructed construction." This type of construction presents barriers that hinder the efficient movement of heat or water, which can be crucial in situations such as fire prevention and sprinkler system effectiveness. When structures are designed in a way that obstructs these elements, it can lead to insufficient coverage from sprinkler systems or hinder the ability for firefighting efforts to control a blaze.

In contrast, closed construction typically refers to the encapsulation of spaces that may limit air flow but does not necessarily imply obstruction of heat or water. Unobstructed construction would denote the opposite, indicating an open design that allows for free flow. Non-combustible construction pertains to materials that resist burning, which is important for fire safety but does not specifically address the issues of heat flow or water distribution. Thus, "obstructed construction" is the most relevant term for the described scenario.