Short Answer
No. Dryer exhaust should be properly routed to the exterior according to applicable requirements.
Detailed Explanation
Dryer exhaust contains not just moisture but also lint, heat, and potentially combustible material. Venting a dryer into the attic creates multiple problems: moisture condensation leading to mold and rot, lint accumulation creating a fire hazard, and heat buildup in the attic. Dryer exhaust must always be routed through a rigid or semi-rigid metal duct to the exterior, with minimal bends and proper clearance. This is both a safety and a building performance issue, not just a moisture concern.
Why It Matters
Dryer exhaust in the attic is a fire hazard, a moisture source, and a code violation. It should always be corrected.
Code & Manufacturer Considerations
Building codes require dryer exhaust to terminate to the exterior. Specific requirements may apply to duct material, length, and clearance.
Building codes and permit requirements can change. Always verify the current requirements applicable to your municipality and project.