Our bedroom has a disused aperture that looks like it was once for an extractor fan. Both ends are covered with a simple plastic grille.
We have serious a noise problem because of this vent. Short of filling it in with concrete, what would be an effective and easily available material to quickly and easily fill the hole in the wall?
Best Answer
Rigid Foam Insulation Cut to fit the gap, use as many layers as needed, cover with the grille. If you determine that you will never need the hole again, take off the grille and finish the wall with a drywall patch or (if the wall is made of some other material), paint the foam directly (many types can be painted) or (lazy way out) hang a picture over it.