What should not be open to the attic in a chase cut through eaves?

In the context of chimney and venting systems, it is important to understand the implications of how open areas in a chase can affect both performance and safety. The entire chase should not be open to the attic because this could create a pathway for heat and harmful combustion gases to escape into the living space of the attic, posing a fire hazard and negatively impacting air quality. Proper sealing and construction of chases is crucial for maintaining the integrity of the enclosure and ensuring that any exhaust is contained within the venting system.

A properly designed chase should restrict the escape of gases; therefore, access points must be carefully considered. While the base or top of the chase may have different requirements for clearance or access to the flue, keeping the entire chase open compromises safety. Access panels are specifically designed to allow maintenance without sacrificing the effectiveness of the chase, meaning they are acceptable if used appropriately.

Thus, maintaining a solid structure for the chase that limits open access points is essential for proper function and safety in chimney and venting systems.