The answer to 'roof decking leaking' is that a leaky roof decking is often caused by water damage, rotting wood, or poor installation. Symptoms may include water stains, mold growth, or sagging in the decking. Solutions can range from repairing small areas of damage to completely replacing the roof decking, depending on the extent of the issue.
If the leakage is limited and the damage is minor, some homeowners may be able to DIY the repairs. However, for more significant problems or if you are unsure of the cause, it's best to hire a professional roofing contractor. They can properly diagnose the issue, determine the best course of action, and ensure the repairs are done correctly to prevent further damage.