How do I block noises from a large air vent?

Question

There is a huge air vent between my room and my roomates. There is absolutely no privacy when it comes to sounds. Is there anything I can do to block the air vent between our rooms and still have ventilation?

Answer 1

Hello Arianna Duve:

As sound travels via air, it is impossible to block all the sound and still have ventilation, however you can minimize the transmittal of noise a little. If the grilles are right across from each other, you can move one down or up the wall using the space between the wall studs as a make-shift duct. Think of a periscope; one grille is high, the air travels down between the studs and out the other side.

Patch the hole left by the moved grille, and you will reduce the sound by 50%. If you can line the space between the studs with fiberglass insulation, it will absorb more of the sound. Make sure that you don't block the air movement with the insulation.  

Check with the property owner before you do this!