What type of tubing must be installed in continuous lengths or joined through heat fusion?

The requirement for polybutylene tubing to be installed in continuous lengths or joined through heat fusion stems from its material properties and the need for reliable, low-leak connections. Polybutylene is a thermoplastic resin that is flexible and suitable for hot and cold water distribution. When installed in continuous lengths, it minimizes the number of joints, which are potential points for leaks.

Heat fusion is a preferred joining method for polybutylene as it creates a seamless connection during installation. This process involves heating the ends of two pieces of tubing and then pressing them together, allowing them to bond as they cool. This method ensures a strong, leak-proof joint and preserves the integrity of the system, which is critical for any plumbing or mechanical installation.

Other types of tubing such as PVC, copper, and steel have different joining requirements and do not use heat fusion in the same way. PVC typically uses solvent welding, copper is generally soldered or brazed, and steel is often joined using threaded fittings or welding. This is why polybutylene is uniquely specified for installation in this manner, reinforcing its effectiveness and safety in plumbing applications.