Rock Wool Old Dog New Tricks?

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Permalink Reply by Bud Poll on February 4, 2013 at 1:33pm

Hi Richard,
I'm not sure about your reference to "Ridgid" rock wool. I'm somewhat familiar with Roxul which is a high density cavity insulation and I like it. As for basements, there are SO MANY other considerations, but yes, for a layer inside of some rigid foam panels it looks good.

Bud

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Permalink Reply by George J. Nesbitt on February 4, 2013 at 8:28pm

Rock wool is available in rigid product, with various densities, depending on application.

There is a product designed as drain board for foundations.

It's available in pipe insulation, batts, and blown in. Although you may have a hard time finding or getting.

Look for industrial / commercial / wholesale insulation suppliers.

It's fireproof & waterproof, lower embodied energy than foam, but has formaldahyde glues still.

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Permalink Reply by Jose Macho on February 5, 2013 at 9:57am

I have used a few brands of rigid batts for air sealing and found the Roxul brand better. Roxul is more dense and easier to cut  and we use it frequently for air sealing in areas where foam will not work and some chase areas. Most brands are marketed as acoustical batting,  however I have seen Roxul reps at the big box stores promoting the product for general attic/wall insulation against fiberglass. For attics cellulose is more cost effective and any rigid  batt (rock wool or fiberglass) used in attic insulation  is problematic. Rock wool has great thermal characteristics and does not wick water making it a good choice for basements and exterior applications. My only complaint is rock wool (slag) fibers are nasty.

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Permalink Reply by Richard Scott Mills on February 6, 2013 at 8:12am

Thanks Jose

For exterior application do you attach directly or with drainage plane?

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Permalink Reply by Jose Macho on February 6, 2013 at 2:23pm

I have not used Roxul for exterior applications- only airsealing and basements. Check their website as I believe Roxul offers additional products specifically for exterior applications

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