The answer to 'why is my roof decking leaking' is that there are several common causes, including improper installation, water damage, or structural issues. Roof decking is the structural layer that supports the roofing materials, and if it becomes compromised, it can lead to leaks and water infiltration.
Some of the most common symptoms of a leaking roof decking include visible water stains or drips, mold or mildew growth, and sagging or soft spots in the roof. These issues may be caused by things like missing or damaged flashing, improper ventilation, or underlying structural problems in the roof framing.