Re: Cheap and Easy way to keep BIRDS out of the Exterior vents
Small screen will create a fire hazard in the case of a dryer vent and will severely restrict airflow, regardless of the vent type. Also, as the screen will be coated with moisture each time it is used, it will collect all the lint and dust that should be venting to the exterior.
A better solution would be to use 1/4" hardware cloth. Cut it larger than the vent shroud and bend it to fit over the outside. The hardware cloth will likely stay there on its own, at the most use a screw to hold it in place. This will not restrict airflow of the vent, however it will need to be serviced on a regular basis to remove trapped lint and dust.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!