The answer to 'why is my roof decking worn out' is that the roof decking, which is the structural layer of the roof beneath the shingles, can become worn out over time due to a few common causes. The most frequent reasons are water damage, age, and poor ventilation.
Water damage is one of the primary culprits of worn-out roof decking. Leaks in the roofing system can allow water to seep through and rot or deteriorate the decking. This is especially common in older homes or in areas with heavy rainfall. Another common cause is the natural aging of the decking material, which can become brittle and cracked over time, even without water exposure. Finally, poor attic ventilation can lead to excessive heat and moisture buildup, which can also damage the roof decking.