Soundproofing Windows with a “Plug”
Windows are the most common sources of admitting noise into (or out of), a room. Glass panes and wood window frames seem to be almost invisible to sound. An alternative to replacing the window with double pane glass, (a noise reduction of about 20%) or vinyl frames, (noise reduction of about 30-50%), is to make a removable “plug” to block the sound coming through the window. While this will also block light, it won’t matter if the window is a bedroom and the noise is keeping you from sleeping. If light is wanted for day use, make the plug removable. It can then be taken out to allow light to enter the room. Here’s how:
Measure your window frame to see how much depth there is to the sill. This will determine the thickness of the material you can use. The mat is cut from rolls that are 4′ wide and is sold by the running (linear), foot. So if your window was 4′X4″, you’d need 4 running (Lineal) feet of it. If you window is an odd size, like 4′X4’5″, order to the next largest half foot size: 4′X4’6″
Usually, one thickness of 2″ “Super Soundproofing Mat” will do. The mat is relatively stiff, but windows over about 3′X3′ may need a “backing board”. This is simply some lightweight wood or fiber board to attach the mat to. Use contact cement. Cut a few holes in the back for your fingers to fit while handling the plug.
The plug should fit the window opening very tightly without cracks which will permit sound to enter the room. It probably won’t matter which way it is inserted, but if you place the soundproofing side out and the carrier board side in, you could add more soundproofing mat to the room side, if needed. If you put some on the outside, make sure it’s cut an inch or two oversize to help block the sound that may come through the edges of the plug and the window frame. A space here helps the soundproofing effort! Make sure your window panes and frame are well sealed, no air gaps!
To make the plug easy to handle, if you intend to remove it, attach some cabinet handles to it so you can easily grip it will be lightweight enough for a woman to handle if you use thin boards and plywood and the window frame isn’t very large. An added bonus of such a soundproofing plug is the thermal insulation property of the window goes way up, keeping you warmer in winter and cooler in summer! A 1″ layer of our Super Sound Proofing Mat” is about R-5.5 so it wouldn’t take too many layers to equal a very high “R” number. (The R number refers to the heat insulation quality of a material).
If the window is exposed to full sunlight all day, it may be prudent to help limit heat buildup between the glass and the soundproofing mat by first lining the window and mat with aluminum foil as a reflector. The mat can withstand temperatures of over 200*F so don’t worry about it, but what you leave in the airspace might suffer- (plants, shades, blinds, etc)! You can get an idea of the heat buildup in the airspace by sliding a oven meat thermometer thru the mat and into the airspace. While not totally accurate, it will give you an idea of the heated air in the space.
If large amounts of sound are being passed by a window, either way, (playing the drums?), more drastic measures may be needed. This could entail lining your plug with a limpid material to give it more mass. If a plug as described accomplishes the purpose, it may make sense to leave it in place rather than to make it removable. In that case it can be sealed by caulking it around the edges, which will help the soundproofing sealing job. A better material for this is our “Super Soundproofing Floor Mat”, a “loaded” vinyl with a foam backing.
We have the mat in 1 1/2″ and 2″ thicknesses, which are firm enough to push into place in the smaller window frames without a backing board. A dab of cement like household “Goop” will hold the mat in place, if needed. If you intend to leave it in place, caulk around the edges.
You might also consider a shutter for the outside of the window if it’s practical. 3/8″ Plexiglas will work, but must fit well! Many times this works quite well.
Alternatives/additions to this is a “Interior Window“, (we now can supply acrylic panels and magnetic edging so you can make your own or we’ll make it for you), one that fits overyour existing frame and window or “Acoustical Curtains” either vinyl or fabric to hang over the window opening. Remember, optimally, a dead air spacing between glass is needed for a real meaningful reduction of sound in a framed window.