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Soundproofing Lies, Course 102


Lies Soundproofing Window Companies Will Tell You

Soundproofing Window Company Lies

Soundproofing window companies will tell you that STC is not important.


  Soundproofing company con man. 

They tell you this because they do not have any STC tests for their own windows.

If they claim an STC number but cannot offer you lab test results, then their numbers are lies.

A Bit About STC Numbers

There are two false sources for STC ratings:

  • Laminated Glass Industry Tests. These are tests performed on laminated glass in a couple of different glass assemblies (glass only tests, not frames). Glass tests alone are not valid for window tests. The testing must include the complete window, frame and glass.
  • STC Tests Performed By The Competition. Some soundproof window companies assume their windows are as good as their competition who may have had the STC tests done. In order for STC ratings to be true and factual, lab tests must be performed on their own windows by an NVLAP (National Voluntary Laboratory Accreditation Program) certified lab.

What To Do?

If a soundproofing window company says they have STC ratings from tests performed by a lab, have them show you the results.

If they won't show you the test, they don't have one.

Continue to Walls and Ceilings.