If an incident commander is unsure of the roof construction type of a single-family dwelling, what should they assume?

In situations where an incident commander is uncertain about the roof construction type of a single-family dwelling, assuming that the roof is lightweight construction is prudent. This is because lightweight construction, such as trusses and engineered beams, is commonly used in modern residential buildings.

Lightweight materials are more prevalent in contemporary construction practices due to their cost-effectiveness and ease of installation. They can also fail more rapidly under fire conditions compared to heavier, more traditional materials. Therefore, an incident commander should operate under the assumption that lightweight construction may be present, which allows for a proactive approach to safety and strategy during firefighting operations.

Understanding the potential hazards associated with lightweight roofs helps incident commanders make informed decisions regarding tactics and resource deployment. By assuming lightweight construction, it prepares responders for a quicker roof failure, emphasizing the need for caution when operating underneath such structures.