Are combustible concealed spaces allowed in Type IV construction?

In Type IV construction, which is also known as heavy timber construction, combustible materials are indeed permitted under specific conditions. This construction type typically includes large, solid wood members such as beams and columns, which enhance structural integrity while providing additional fire-resistance due to their mass.

Concealed spaces can be designed to accommodate electrical, plumbing, and HVAC systems; however, they must comply with specific codes and regulations that dictate fire safety measures. The allowed combustible concealed spaces must be protected with proper fireblocking, and any concealed spaces that may pose a fire risk often require adequate ventilation and materials that can withstand exposure to fire for a specific period.

The emphasis on the safe use of combustible materials in Type IV construction is aligned with the essential principles of fire safety, ensuring that even though there are combustible elements, they are managed in a way to minimize the risk of fire spread and improve overall safety. Thus, allowing for combustible concealed spaces is consistent with the structural provisions and safety protocols defined for Type IV construction.