Heritage Restoration, Inc.

Building Sound Deadening

I live in an old mill building that was converted to condos in the mid 80’s.  I never experience any noise disturbances on either side of me but I hear everything from the unit above. There is no access under the finish ceiling. There is a 3 to 4 foot gap between my ceiling and the floor of the unit upstairs.  The only things up there are sprinkler lines and some wiring. Can I insulate this ceiling? What kind is going to trap heat and more importantly keep the noise out from up above? I don’t plan on being here forever but I would at least like to stop having to walk around with noise cancelling headphones on. Please help!




Sound waves, airborne or by impact, create vibrations that transfer through the air and materials in contact. Airborne sound pushes and pulls the air back and forth.  Impact sound vibrates an object that then travels through the air.  Sound waves lose energy as they travel or they can be absorbed.  So where you are the tenant below, next to or above, the goal is to reduce the vibrations at the source and/or dampen the vibrations through materials to reduce the sound.


Sound from Above

There is the quick and less expensive or the comprehensive and well, it costs more.  The most effective sound dampening would be achieved through a combination of retrofits.  To give you an idea of effectiveness, wood framing with ½” drywall has half the sound dampening effect as a combination of staggered independent framing, insulation, and a double layer of ½” drywall.


In Between the Framing

There are more flexible sounds barrier materials that can be stapled under existing subfloor or woven between the framing to reduce airborne sound.


Resilient Channels

Typical cost effective wallboard sound reduction comes from the finish drywall surfaces. Acoustically effective resilient channels are designed to absorb vibrations, and are installed on top of the framing and under the drywall.  You can put the resilient channels on top of the existing drywall and install another layer of drywall.



There are a variety of insulations that effectively reduce sound vibration, some better than others.  Insulating for sound is opposite from insulating for energy, where the denser the packing, the better the sound reduction.


Over the Frame

Commonly hotels use resilient channels and two layers of ½ inch drywall between floors and walls.  A sound absorbing mat can be applied on the first layer the same method as wallpaper.  As an alternative you can use a layer of sound deadening board (made from compressed wood fibers), under a single layer of drywall.  For better results, the second layer can be attached using a construction adhesive.


Sound Under Foot

Under The Finish Floor

A sound absorbing mat is the best material for blocking impact sound under the sub floor, which goes on top of the frame, or joists. Tile, carpet or wood or any other finish floor can be installed above.



Carpets with thick piles are effective at reducing sound transmissions to rooms below.  A sound deadening carpet padding can also help dampen sound vibrations from one level to another.


General Room


Certain windows can transfer quite a bit of noise, as well as reflect noise inside a room. Heavy curtains work best to absorb inside noise and reduce outdoor noises. Thicker fabrics, such as velvet, are optimal; layer curtains for the best results.


Outside noise can also be reduced through storm windows that use felt weather stripping between the metal parts as a sound dampener.



Blank walls create the most echo.  Rooms can be broken up with furniture, wall hangings or well-placed solid objects.  The more clutter, the less echo.


So good luck Rachel.  May you can listen to music from real speakers soon.

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