Put an End to Exhaust Vent Chatter
Attach a few small magnets first and then run the dryer, hood vent or bath fan to make sure the flapper still opens. If the chatter is gone, great. If it persists, add another magnet. Always check that the flapper still opens when it’s supposed to. Once you get the right balance, add a dab of adhesive to the magnets to keep them in place. You can get a 1/2-in. x 30-in. magnetic strip at home centers for a couple bucks.
For noisy plastic vents, try attaching small washers with a dab of clear silicone. Note: These flapper-quieting tips are not for use with gas appliances. Plus: Check out these 100 essential cleaning hacks all homeowners should know.