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Blow-in cellulose and your hollow walls

It's not too late to insulate. 

A few years ago, most American homes had no insulation in them. When a homeowner did insulate, it was usually with fiberglass batts.

Then along came some better products. One of them is blow-in cellulose insulation. Does it work? I can attest to this: YES. I've used it in walls and ceilings, and it works quite well for airborne noise. If you live in an uninsulated home and you hear your neighbors voices coming through your walls or ceilings, cellulose will dampen that noise or mute it entirely.

It doesn't work for all types of noise.

But it doesn't eradicate impact noise. You might still hear the sounds of someone walking across a bare hardwood floor with their shoes on, for example, or hear wall-mounted cabinets opening and closing. There are other solutions for that, and by combining different solutions you can control most structural noise and create more privacy.

Low cost

Blow-in insulation is inexpensive. You can hire a specialist to do it, or as this YouTube video by Craig Wolfe shows, you can do it yourself with rented equipment. As you'll see in this video, cellulose provides much denser and comprehensive coverage than fiberglass batts. They actually blow additional cellulose into the wall cavity with a fiberglass batt already in it to show you how much air space was still available.

No demolition. Takes only a couple of hours.

What's really great about blow-in cellulose is that you can keep your existing walls. You just need to cut some small holes into the drywall, which you can replace afterwards, and blow the insulation into the cavity.

This promo video on Cocoon Insulation shows how cellulose fiber is fire retardant and because of its density, very effective at noise control:


  1. Thank you very much for providing this information. The walls of my home are very hollow, and noise carries through the house. I like what you said about blown-in insulation being effective and inexpensive. That really appeals to me.

    Susan Hirst |

  2. It`s a great video and well explained about the use of Attic insulation. It not only reduce the noise, but it is also fire resistance. To know more about inner wall insulation visit Energy Home Pros.

  3. Foam Spray Insulation Ltd is a professional insulation company which has been trading for over 25 years. home foam insulation is a key way to protect your home from heat loss, reducing energy bills and helping the environment.

  4. This is a great post. I like this topic. This site has lots of advantage. I found many interesting things from this site. It helps me in many ways. Thanks for posting this again Garage insulation contractorsWe provide commercial spray foam insulation for several different commercial building structures because we are best commercial insulation company, call us now!

  5. I know no article is perfect, but yours is as close as it gets.Interesting informational articles like this are rare. This material is informational without being boring and intimidating. Thanks for posting this again. Fireproof spray foam insulation in toronto

  6. This comment has been removed by the author.

  7. Great Information about blowing cellulose insulation into your walls. I know personally it works great! did you know spray foam insulation works much better at sealing up the cavity? You can find a specialized spray foam insulation company that can inject foam into these hollow cavities without removing the drywall

  8. Actually, no, spray foam is not better. These posts are spam, but in case anyone reads them seriously, the best spray-in insulation is cellulose, and the best soundproof batts are rock wool.


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