Final answer:
Heavy timber construction in accordance with the NBCC avoids the use of combustible materials and ensures structural stability in case of a fire by utilizing large timber members and fire-rated materials.
Step-by-step explanation:
Engineering
According to the National Building Code of Canada (NBCC), heavy timber construction avoids the use of combustible materials such as untreated wood beams and columns. Instead, it utilizes large, heavy timber members that have a higher resistance to fire and provide structural stability in case of a fire. This is achieved by using specific assembly and construction methods, such as concealed spaces, fire-tolerant connections, and fire-rated materials.