Windows are _disibledevent="mso-spacerun: yes">  A soundproof window is a second laminated window (two sheets of glass with a clear plastic membrane sandwiched between) which is then installed behind your existing window, with a dead airspace in between. The second window should mimic your existing window. So, if you’re seeking fresh air you will have to open the two sets of windows to allow the fresh air in.  This type of setup is very effective at shutting out the noise out giving you an 80% or more reduction in noise.  Double pane windows are not as effective at reducing noise and may only reduce noise up to 20%.