Final answer:
It is false that SIP buildings do not require a separate air or vapor barrier. SIPs can be airtight but completely depend on expert sealing to achieve a code compliant air barrier.
Step-by-step explanation:
The statement is false. Although Structural Insulated Panels (SIPs) are known for their high performance regarding insulation and air tightness, a separate air or vapor barrier may still be required to meet building code requirements.
The need for an additional air or vapor barrier depends on the sealing quality of the SIPs and the specific building code that applies to the construction.
SIPs can achieve a perm rating of less than one perm if they are properly sealed. However, ensuring that all joints, seams, and penetrations are perfectly sealed is imperative to create a code compliant air barrier.
When the joints between the SIP panels are properly sealed, they create an effective air barrier. This eliminates the need for an additional air or vapor barrier in the construction. SIP buildings have a permeability rating of less than one perm, which means they meet the requirements of building codes for air barrier performance.