Get matched with top insulation pros in Lake Winnebago, MO

STC (Sound Transmission Class) is a rating that describes how well a building material or assembly blocks airborne sound. A higher STC rating means less noise will pass through the material, providing better sound reduction. This rating system applies to various building components, including windows, doors, flooring, drywall, and insulation.

For context, a typical single-pane window has an STC rating of around 25 (where normal conversations are audible), while a well-sealed, double-pane window can exceed STC 45 (blocking loud speech and most music). It is important to note that for some products, like soundproofing drywall, the STC rating refers to the entire wall system, not just the individual panel.

Additionally, STC ratings are most effective for measuring sound reduction at mid-to-high frequencies, such as human speech, and may not accurately reflect how well a material blocks low-frequency sounds like bass music or thunder. Because of these factors, it is recommended to consult a professional to determine the right STC-rated materials for your specific soundproofing needs.

You do not always need to remove old insulation before adding new. If the existing insulation is in good condition—not wet, physically damaged, moldy, or infested with pests—you can add new insulation directly on top of it for a compounding effect. You can also mix different types, such as adding blown-in insulation around existing fiberglass batts.

However, removal is recommended if the old insulation is compromised by water damage or pests. You should also remove it if you plan to install a different type of insulation, like switching from roll or batt insulation to spray foam. If the existing insulation is very old or damaged, you will likely get more benefit from removing it and starting fresh.

If you have bubble wrap lying around the house and you don’t care about the odd look, taping bubble wrap over a window is a very affordable way to insulate it. Another inexpensive option for insulating windows is to add new caulk around the glass. This step quickly cuts down on air drafts for older windows, and a tube of caulk only costs a few dollars. Adding plastic shrink film around the glass is another cost-effective option. You can purchase a kit of plastic film for a few dollars per window.

For your safety, you should always wear a mask when cutting batts of fiberglass insulation. We also recommend wearing eye protection, safety gloves, and long sleeves to protect your skin. Properly suiting up helps you avoid several fiberglass issues, such as cuts from the tiny shards of glass and inhaling small bits of fiberglass.