Read Our Analysis to Find the Best Soundproof Windows. To compare which windows are best for noise reduction, you want an objective standard \u2013 a Sound Transmission Class (STC) rating. An STC rating measures how much sound (in decibels) that a window blocks. The higher the number, the better. While increases may seem small, each increase of 10 in an STC rating halves the sound. Single-Glazed Windows Single-glazed windows are made of one window pane. They have an STC rating of 26 to 28, which means that you can hear soft speech clearly through the window. They block very little sound because they are thin and have the least mass of the windows analyzed here. Double-Glazed Windows While double-glazed windows stop more sound than single-glazed windows, they don\u2019t block as much as noise reduction window inserts. Double-pane windows have an STC rating of 26 to 32. This means you can easily hear loud talking through the window. Double-pane windows have two layers of glass with an air gap in between them so they block more sound than single-pane windows. Thicker windows, in addition, to stopping more sound, also provide more insulation because they have more mass. Storm or Impact Windows An impact window has an STC rating of 32 to 35. Impact windows, or hurricane or storm impact windows, are designed to withstand rain, high winds or falling objects and to stay intact without spraying shards even if they break. They\u2019re generally made of two pieces of tempered or laminated glass held together with a plastic membrane. They also have frames from heavy-duty materials such as aluminum or vinyl, and they\u2019re more strongly adhered to the glass with a silicone glazing process. While they are ideal for stopping wind damage, they don't do a lot more than double-glazed windows to stop sound. Plastic Noise Reduction Window Panels Acrylic noise reduction window panels have an STC rating of 42. Lower cost than replacing your windows, they can cut the noise. However, acrylic is plastic and easy to manufacture but also easy to scratch, and it yellows over time. Sun and Sound Windows used to offer plastic noise reduction window panels; however, customers reported lower satisfaction rates with this option than with laminated glass noise reduction window panels. Laminated Glass Noise Reduction Window Panels Laminated glass window inserts have an STC rating of 48, higher than acrylic noise reduction window panels. With an STC rating of 48, loud speech is largely inaudible. They are made of two layers of glass held together by a membrane, which helps it dissipate noise vibrations. In addition, our 1\/4\u2033 thick laminated glass is denser and has greater mass than 1\/4" acrylic, meaning it stops more sound. With acoustic grade laminated glass inserts, our customers reported a 95% satisfaction rate. Getting the Best Noise Reduction Window Is Also About Installation How you install window inserts is important because you need a good sound trap. There are three elements of a good sound trap: mass, air gap and seal. Sufficient mass \u2013 Our laminated glass is made from two 1\/8\u2033 thick pieces of glass, held together by a flexible membrane, to form one solid piece of glass slightly more than 1\/4\u2033 thick. The membrane keeps the glass from vibrating with sound waves. A good air gap \u2013 The two-inch air gap we use is a good rule-of-thumb when trying to stop the sound that you find annoying. The bigger the gap, the more sound waves are trapped. A good seal \u2013 The seal of our soundproofing window inserts is important because sound can act like water, seeping through openings. Our infiltration rate is less than .01 cfm\/lineal foot, which exceeds the International Energy Conservation Code (IECC). As a bonus, the air gap also insulates against energy loss. Our soundproofing window inserts add an R2.5 to your existing window. For example, when installed over a single-pane window, the R rating increases to 3.3, the same as a double-pane, argon-gas-filled window. That is a 60% increase in energy savings per window. Sun and Sound Glass Noise Reduction Window Inserts Our windows block noise from street traffic, airplanes, construction, lawn equipment, loud music and air-conditioning units so you can enjoy quiet in your home. Unlike impact windows, they don\u2019t change the look of your home (and are approved for historic houses), and we can usually install them in just a day with no mess. See other questions to ask when considering purchasing noise reduction window inserts, or talk with a team member today for a free estimate.