Obstructed construction includes ____________ construction.

Obstructed construction refers to types of building structures that can impede the effective distribution and functioning of fire protection systems, such as sprinklers. In this context, wood joists are considered obstructed construction because they create spaces and voids that can hinder the flow of water and the coverage area of sprinkler systems in a fire event.

Wood joists often have a significant width and are placed a certain distance apart, which can limit direct access for sprinklers to spray water effectively on a fire. This construction method can also trap smoke and heat, making fire suppression more difficult. Therefore, understanding the impact of various construction types on fire sprinkler performance is essential for ensuring optimal fire safety and compliance within building codes.

The other construction types, such as open-grid ceilings and smooth ceilings, typically present fewer obstructions to sprinkler spray patterns and are thus less likely to interfere with fire suppression efforts.