The answer to 'roof decking leaking' is that the most common causes are water damage, rot, or improper installation of the roof decking. Symptoms can include visible leaks, water stains on the ceiling, or soft/spongy spots in the roof. Solutions may involve repairing or replacing the damaged roof decking, addressing any underlying issues like leaks, and ensuring proper installation and ventilation going forward.
Roof decking problems can be a serious issue, so it's generally best to have a professional roofing contractor inspect and diagnose the problem. They can determine the extent of the damage and recommend the appropriate repairs. DIY roof repairs are possible for minor issues, but more significant problems should be handled by experienced professionals to ensure the safety and integrity of your roof.