I feel like there must be something wrong with my ductwork. When the cooling is on, the bathroom ductwork rattles. Anywhere else in the house the air conditioning is on and silent. I just feel great AC when I sleep, watch TV or make a meal. When I go to the bathroom it sounds like the dryer is on with all the rattling. All I can think is that there must be a loose bolt in that piece of the ductwork. Only in the bathroom is the noise and it is super loud. It is all you can hear when you shower or brush your teeth. I am hoping the fix for the ductwork is very small, but I don’t see how. How can my HVAC contractor access the bathroom ductwork? It sounds like the issue is with the air duct right above the shower. The opening vent to the air duct is quite far away. I know ductwork sealing is done with a gun like device. It shots into the air vent air filled with sealant particles. I know the air can go quite far in the ductwork, but that far? Also I don’t think it is a simple crack or tear along my HVAC duct. I think there is a major thing going on like the ducts are not hooked right or fastened together properly. So I think my HVAC professional will need to tear down my wall to access the issue. Then perform the repair and then put new wall over top. That is a lot of money for a rattling sound.