Under what condition is above deck thermal insulation permitted?

Above deck thermal insulation is permitted when it is covered with an approved roof covering. This requirement ensures that the insulation is adequately protected from environmental factors such as moisture, UV radiation, and other elements that could degrade its performance and reduce its effectiveness. By using an approved roof covering, it also aids in maintaining the integrity of the building envelope, which is crucial for energy efficiency and the longevity of the roofing system.

While flexible coverings, below-grade insulation, and non-combustible materials might be relevant in different contexts or applications, they do not specifically address the conditions under which above deck insulation should be utilized and protected. The primary concern in roofing systems is ensuring that any insulation installed above the deck remains durable and effective throughout its intended lifespan, which is why proper covering is emphasized in building codes and standards.