Type IV construction should be built without?

Type IV construction should be built without?

• A. Concealed spaces
• B. Fire doors
• C. Windows
• D. Attic ventilation

Answer: (A)

Type IV construction relies on large, exposed timber members and aims to limit hidden pathways for fire. The key rule here is to avoid any concealed spaces—no hidden voids in floors, ceilings, or walls. Concealed spaces can trap heat and allow fire to spread unseen, making it harder to control and to protect the structural timber. By keeping spaces open and free of hidden cavities, the fire performance of heavy timber assemblies remains more predictable, and firefighting access to surfaces is easier. Fire doors, windows, and attic ventilation aren’t the defining restriction for this construction type; they can appear depending on design and code requirements. The defining feature for Type IV is the absence of concealed spaces.

Type IV construction relies on large, exposed timber members and aims to limit hidden pathways for fire. The key rule here is to avoid any concealed spaces—no hidden voids in floors, ceilings, or walls. Concealed spaces can trap heat and allow fire to spread unseen, making it harder to control and to protect the structural timber. By keeping spaces open and free of hidden cavities, the fire performance of heavy timber assemblies remains more predictable, and firefighting access to surfaces is easier.

Fire doors, windows, and attic ventilation aren’t the defining restriction for this construction type; they can appear depending on design and code requirements. The defining feature for Type IV is the absence of concealed spaces.