How to Soundproof Interior Walls

In today’s Practical Sustainability segment, John and Matthew look at a variety of materials and techniques used to soundproof interior walls.

  • Sherry

    Do you have any information on the relative effectiveness at soundproofing of these different approaches? We will be building in the near future and soundproofing is an issue we’ve been talking about. My husband wants to use the special soundproofing drywall, but I’d like to know if some of the lower cost options might come close in effectiveness.

  • Matthew North

    Sherry – that is an excellent question! The most effective types of sound insulation are also the most expensive – the “quiet roc” sound proofing drywall that your husband wants to use will be expensive. However, I’m not sure you would need to use this everywhere. In our projects, we specify the various types of sound proofing in a home depending on the actual requirements and conditions. We have found that insulating the interior walls with regular batt insulation is the most cost effective and works well. We now try to insulate with standard batt around all the interior walls in a new home or remodel because it only adds a few hundred dollars to the total insulation bill. A step up would be to use the denser “Roxul” insulation – we would use this around media rooms or other spaces that have a high noise transfer. Spray foam is more expensive than “Roxul” to apply and requires backing but is really effective around plumbing drains and stacks and hard to reach areas – for instance we used spray foam in a dining room ceiling where the master bathroom was above to dampen the sound of the water running and we were pleased with the results. The “quiet roc” sound proof drywall is very expensive but worth it in certain applications. For a whole home, it would be several thousand dollars more than regular drywall. We used “quiet roc” on a renovation to an attached town house – we used the sound proof drywall along the entire party wall because the home owners were really concerned about noise between the units – also, we used “quiet roc” on another home to sound insulate around an attached garage and a music room (the children played the drums so you can imagine the noise concerns!) In both cases, it was well worth the money spent. You can also combine “quiet roc” with “Roxul” to get even more sound proofing. What I recommend is to look at your plans carefully and use the more expensive soundproofing options in areas of high noise transfer and the least expensive soundproofing options in more general areas. Also, remember to think about sound transfer between the floors and ceilings. I hope this helps!

  • Anonymous

    Thanks Matthew! The house will be built in a location just over one mile away from the nearest neighbor and we’re planning to use structural insulated panels and a stone facing, making the house rather amazingly quiet to begin with. The soundproofing will be to isolate sources of noise within the home, like the laundry and the media room.

    I can’t show your response to my husband because you mentioned using quiet roc with Roxul to get more soundproofing! He’ll latch onto this as the best way to go and want to do it throughout!

    Seriously though, are those materials effective enough to block laundry and media room level noise? We’re also planning to place the laundry such that the machines sit on the garage slab rather than on the house floor to isolate their vibration from the main house and not back them up to an occupied room. The media room is a combination media/library and we’ll have bookcases on the walls between the media room and the rest of the house, providing book storage and additional blocking/scattering of sound.

    We like quiet. 8-)

  • Matthew North

    Hi Sherry – sounds like you are taking a lot of well thought out design steps to create a quiet living environment! With regards to laundry soundproofing – the largest issue is vibration as you have mentioned. Another step would be to place the machines on a resilient pad – similar to a rubber flooring material – to further isolate them from the structure of the house – even a concrete floor can transmit sound. For media rooms, I do think that Roxul insulation combined with Quiet Roc is the most effective way to go. We have done this in the past and it seems to work well. We have had mixed results with resilient channel as the sound proofing method. Good luck with the project – thanks for participating in the Slow Home site – your questions and comments are great!

  • james

    how to build a soundproof for for low cost?

  • Matthew North

    Hello James – thanks for your question – the best way to build soundproofing into your home at the lowest cost is to insulate all the interior walls with regular batt insulation and only install sold core interior passage doors that have a minimum air space on the sides and bottom.

  • Matthew North

    Yikes….spelling problems today – sorry I meant “solid core doors” not “sold core doors” !

  • Matthew North

    Yikes….spelling problems today – sorry I meant “solid core doors” not “sold core doors” !

  • Anonymous

    Hello James – thanks for your question – the best way to build soundproofing into your home at the lowest cost is to insulate all the interior walls with regular batt insulation and only install solid core interior passage doors that have a minimum air space on the sides and bottom.

  • Anonymous

    Hello James – thanks for your question – the best way to build soundproofing into your home at the lowest cost is to insulate all the interior walls with regular batt insulation and only install solid core interior passage doors that have a minimum air space on the sides and bottom.

  • http://www.facebook.com/tara.steell Tara Steell

    Hello. I was wondering if you have any insight or thoughts on how to soundproof exisiting built interior walls in a home. I was told spray foam companies like Spraytek can do it but it appears they are no longer in Calgary.
    Thank you

  • virginia

    Tara did you ever get an anwer to this question. Myself as well need to sound proof an already existing room :((

  • Tiger Foam Canada

    Absolutely this can be done with spray foam. There is a great application video on the TigerFoam website for filling an existing wall with spray foam. http://www.tigerfoam.ca/blog/20/Upgrading_Stud_Wall_Energy_Performance_With_Spray_Foam.html

  • http://www.noisekiller.co.uk/ Noisekiller

    Great Video. soundproofing is so very inexpensive

  • Boozemun

    What about new construction where they put nothing in there. Can anything be done there?