When installing a piece of plastic, a metal or wood bead should be used if the plastic dimension exceeds how many inches?

Using a metal or wood bead during the installation of plastic is important for ensuring proper support and structural integrity, especially as the dimensions of the installed sheet exceed specific lengths. When the dimension of the plastic piece exceeds 24 inches, the use of a bead becomes necessary to prevent sagging and to provide a secure fastening point. This is due to the increased likelihood of bending or deforming when larger sheets are used. The bead acts as a reinforcement, creating a more stable and trustworthy installation, which is crucial for durability and performance over time in various environmental conditions. Proper adherence to these guidelines ensures that installations remain secure and functional, reducing the risk of damage or failure.