Myths About Window Glass & Stopping Noise, Part 1

By Randy Brown
Soundproof Windows, Inc.


Most noise problems and soundproofing problems involve windows.  If the trouble with noise is trying to keep the noise outside (or inside) of a home or building, then windows are almost always part of the noise problem. In this article, we destroy some of the myths that exist about what glass has to do with stopping noise by addressing the various kinds of windows and window glass relative to soundproofing levels.

Additionally, some inexpensive tips for soundproofing your existing windows are mentioned here.

When are Windows Part of The Noise Problem?

Myth: Walls are the Noise Problem

If noise is coming through a wall and that wall has a window, then you need this information.  Windows are always a bigger part of the noise problem than the walls are.

Until the windows have STC values in the 40s, the condition of the walls don't matter, as most walls have STC values in the 40s. Walls with siding may be more of a problem than stucco, brick, etc.

Unless very strange walls are built, the noise problems and soundproofing problems are first the windows, second the doors and third the wall structure itself.  That is also the order in which the problem should be solved.  Perfect walls and doors will not help with soundproofing to solve the noise problem unless the windows are also improved.

Windows and their STC Values Relative to Soundproofing

Windows & STC Values


STC Value Range
One Window Systems:
Single Pane
Typical Dual Pane
Good Dual Pane
Specialty Noise Abatement
Two Window Systems:
Over Single Pane
Over Dual Pane
Maximized for Noise

Table provided courtesy of Soundproof Windows

Soundproofing and Glass Thickness

Glass thickness can greatly effect how much noise is stopped, and it is also how your soundproofing problem or noise problem is solved.  Thin glass can destroy your noise abatement and soundproofing project.  Thin glass does very little to help noise problems; this is especially true of the lower frequencies. 

You may have thin glass in old single pane windows or in smaller dual pane windows.  Two thin pieces of glass are not much better than one thin piece of glass.  The thin glass vibrates so readily, that much of the noise vibrates right on through the glass.  When you reach 1/8 inch glass, this easy vibration effect starts going away.  Beyond 1/4 inch there is little additional noise value in making the glass thicker.

Single Pane Windows

Myth: Single Pane Windows Let in More Noise than Dual Pane Windows

Regular dual pane windows are seldom better than single pane windows as far as stopping noise. Most people know someone who replaced their single pane windows with dual pane and thought the noise level was reduced. The truth is that their old single pane windows had very bad seals, which let in the noise, not because the dual pane windows were better at stopping noise.

Single pane windows should never be purchased new or as a replacement window.  For the energy efficiency alone, it will be worth it to get dual pane windows.  If for some reason you need or want a single pane window – get at least 3/16ths inch thick glass, though 1/4 inch glass would be better.  If you have single pane windows now, you do not need to replace them because of the noise. 

If you have single pane windows now you can do a few things to help make it quieter. 

  • Seal it as well as you can.  Locking it tightly usually helps. 
  • Caulk it shut if you can (if you do not open it and if it is not needed as an emergency exit). 
  • Putting a plastic/vinyl film on the glass will help a little.  Since it also helps on energy it may be worth it.  Do not expect a lot.  This will help to a minor degree only, but sometimes every little bit helps.

You don't have to replace your single pane windows to achieve soundproofing. An alternative would be to go to a two-window system and avoid replacement.

Click on Soundproofing to continue.