In roofing terminology, what is a Batten typically used for?

A batten is primarily used as a fastener for roof membranes, particularly in roofing systems where battens are installed over a roof deck. They serve as structural elements that support and secure the roof covering materials, ensuring they are held in place effectively. This is crucial for maintaining the integrity of the roof and preventing water infiltration.

While options regarding insulation, decoration, and ventilation may reflect certain aspects of roofing design, they do not accurately describe the primary function of battens. In roofing applications, battens are essential components that ensure the proper installation and stability of the roofing membrane, making option B the appropriate choice.