If venting outside isn t an option you can vent the dryer out of the attic through the roof using a special roof vent to keep rain out.
Dryer vent into the attic fixed.
Home clothes dryers don t start out venting into an enclosed space because the building code specifies that the termination of a dryer duct must be outside.
You should then measure a small hole in the ceiling to fit the dryer vent into.
When venting dryers for long distances use rigid metal pipe with as few elbows as possible.
Be careful you don t cut through any studs electrical wires or pipes in the process.
Here s what the florida building code fbc residential edition says about it.
The international residential code allows you to run a dryer vent through the attic but you can t terminate it there.
If you find that it is not you can adjust it.
Support the ductwork adequately to maintain this pitch don t allow the ductwork to sag in the middle.
Continue the ductwork horizontally through the attic to the closest exterior wall.
Doing so would fill your attic with warm moist air that could rot the framing.