Wet material should be removed from a job site. You never want to use wet material when working with a roofing system. Wet materials in roofing systems can seriously affect its performance. Wet materials can also promote the growth of mold.

When insulation gets wet it even loses its R-value. Wet insulation should never be used. Some components like metal can be dried out without causing permanent damage to the material. Just make sure the metal are not rusted or corroded before installing them.