Blocking unwanted sound through a wall, floor or ceiling is the most common requirement we are faced with. Traditional answers have been pretty amusing, and unfortunately not very effective. You may have heard some of these already: pack it full of insulation, add additional layers of drywall, put carpet on the wall, use egg cartons, fill the wall with expandable foam and our favorite – use ear plugs! There is are several more effective ways to block sound.
The difference between noise blocking and noise absorbing.
Absorbing noise is based on allowing noise to pass through a product and is measured in NRC, Noise Reduction Coefficient.
To create privacy between rooms, noise needs to be blocked, not just absorbed. Noise blocking requires mass, mechanical isolation / decoupling and air spaces. Noise blocking is measured in STC, Sound Transmission Classification.
Ways to Block Noise
The creation of a mechanical break will provide the highest performance partition, and can now be created at the lowest possible cost (see our Sound Isolation Clips) for floated walls and ceilings.
Better than more layers of the same material, sound is actually confused by layers of dissimilar materials. Lab testing has shown repeatedly that changing densities, thicknesses and using larger airspaces will always produce better soundproofing results. Excellent products to be used for this approach are Green Glue and our Soundproof Barrier.
Addressing Some of the Sound Blocking Myths
Insulation of any kind is lightweight compared to drywall. Provided you are using a soundproofing product like the ones we sell, you will never get an additional benefit from high priced insulation.
Egg crates are useless for noise control. Sound passes through as though they don’t exist.
Carpet on the wall is a stone-age solution to sound control. The use of carpet may absorb some noise in the source room, but will not stop noise from getting next door.
Closed cell expandable foam is the worst thing you can do for noise! Expandable foam is lightweight and will actually connect everything together, creating a perfect sound transmission path for all noise.
More drywall is not as effective as one might think. Adding mass is very important in blocking sound above 2000 Hz, but a more rigid partition will actually transmit vibration and low-frequency noise is able to vibrate through even a concrete wall.
Ear plugs work great for stopping noise. I said ear plugs work great for stopping noise! Take out your ear plugs so you can hear me.