What type of construction is commonly linked with an increased risk of collapse during a fire?

Lightweight construction is often associated with an increased risk of collapse during a fire due to the materials and structural methods typically used in its design. Lightweight construction frequently employs engineered wood products such as trusses and I-joists, which provide strength and efficiency but can fail rapidly under high heat conditions. These materials have lower thermal mass compared to heavier, traditional materials and can lose their structural integrity more quickly in a fire.

In contrast, reinforced concrete and masonry possess significant fire resistance due to their dense and heavy composition, mitigating the risks of collapse even under prolonged exposure to heat. Steel frames, while they can lose their strength when exposed to extreme temperatures, tend to have a higher fire resistance than lightweight materials and are often equipped with fireproofing measures. Therefore, lightweight construction poses a distinct concern for firefighters due to its quick failure rate during fire incidents.