Latest Discussions : Miscellaneous


08:24AM | 04/19/06
Member Since: 04/18/06
1 lifetime posts
I am looking at buying a house with rockwool insulation in the attic, 6-8" loose fill, like cellulose. I've read taht depending on the age of the material(which is unknown, but probably not recent) this can contain asbestos or can otherwise be cancer-causing. The owner doesn't want us to test the material for asbestos. We are wondering how much it might cost to remove this kind of material, if it is hazardous. Thanks.



11:25PM | 04/23/06
Member Since: 07/01/03
549 lifetime posts
mineral wool a.k.a. rock wool is a silica based stranded insulation, very similar to fiberglass. Asbestos is a fiberous form of silica, and traces of material that appear similar to asbestos under polarized light microscopy may suggest a small asbestos content. Personally, I have never gotten a positive result form sampling mineral wool, but its not unheard of. A small bulk sample can establish the presence or absence of asbestos, and is very inexpensive. Request it before you buy as a condition of purchase.

Rock wool is a skin, eye and respiratory irritant and needs to be handled with gloves and respiratory protection. Removal is not regulated, and can be accomplished with commercial vacuum service. I don't know the cost, but somce it is not specifically hazardous, you are paying labor and equipment rates; not removal specialist rates.


07:47AM | 02/10/08
Member Since: 02/09/08
1 lifetime posts
this is a very old post, however, correct info needs to be posted. I am the manufacture rep for rockwool..If you need info regarding insulation, go to NAIMA's can also go to of course is made of slag, which is a recycled steel product, and rock, a trap rock mined in Texas...those are the only raw materials in rockwool insulation..we use "coke" which is a recyled material from is used to make the heat hotter in the manufacturing process, in order to save energy...rockwool is the safest insulation on the market also has one of the best thermal insualting properties as well as a superior sound control while not supporting mold or mildew..all while not having to add any chemicals...many other insulation products on the market today are either all chemcial, foams, or have chemicals added to them to keep them fire retardant, cellulose...

Janese Creech

Amerrock Products, LP



05:15AM | 11/29/10
Member Since: 11/28/10
2 lifetime posts
My first experience with Rockwool was back in 1986 when I was removing and remodeling a kitchen. The house was a Tudor built in the 1940's in Yonkers NY.

After removing the wallboard it was discovered that the vapor paper was still in good shape with the Rockwool graphics (cartoony) and product description still perfectly legible. However, thats all that was there (paper), the fiber stuff had decomposed to a sratchy yellow powder and was laying in the bottom of the wall bay on the floor plate to a depth of about 1". The realy bad part was when I removed the wall cabinets and it turned out that the soffits were filled with what I assume to be the same crap. When it poured down from the attic it was like a total solar eclipse (the light left the room). I spent the next three days hacking out my lungs. Whatever that stuff is, it will take you to the next level of hypersensitivity in a hurry. Don't let anyone tell you this stuff is safe. I have not been the same since. I never had a problem with insulation till that day but ever since I have been deathly allergic to spun insulations.

My house in Maine is a 1950's 'Craftsman House' and it is also equiped with Rockwool. I have heppa-vacced it out wherever I have renovated however I have not found the same level of decomposition as in the older house. The 1950's Maine house also has an asbestos lined chiminey wich we were able to have the cost of the house adjusted down after testing was proof possitive. Unfortunately the sellers were only willing to grant enough money for encapsulation of the chiminey and not the total removal/replacement of the chiminey. The loose insulation from the mid 20th century was practically wortless by todays standards ( dung and hay would work better). Even when it was new it looked somthing like modern insulation after a racoon had raised a litter of pups in it. I would always try to get a discount for the removal/replacement when buying an old home. When removing, try if possible to open an end of the attic to allow cross ventalation (an exaust fan would be tops) and drop the stuff directly outside rather than carry it through your home. A good way to do it is to set up a dust collector outside the house and have a worker to shut off the machine and change bags as they fill up. A narrow plasic car trunk shovel works good for shoveling the easy stuff out of the ceiling bays but avoid brushing as this raises allot of dust.

Best of luck, Matt Corwin


12:34PM | 01/02/13
I have a layer of this in my attic which has been covered with loose blown fiberglass...and it's growing mold perhaps some other alien intelligence/ malevolence;)

Considering my natural repulsion to fiberglass batt, seems like common sense blown fiberglass is a terrible idea, but I don't have the funds to replace all this material right now, and temporary encapsulation/ isolation is definitely needed for both layers.

I don't "blame" these materials for the mold and other pathogens, previous roof leaks and animal intrusions/excretions seeded those, but the air quality in this house is poor to uninhabitable, and I'm wondering:

1) Is there some kind of fumigant or spray I can apply to kill pathogens and trap dust? I'm thinking aling the lines of a humidifier filled with a bleach solution, and I attempted a pump-sprayer application of diluted Elmer's glue;) but it was too viscous.

Didn't try diluting it with bleach just water;)

2) I bought several hundred yards of 3'wide body shop masking paper, thinking it'd be better for breathing moisture than plastic, any comments about the effects of rolling that out?

No liability assumed for advice/ speculation: I presume any will be taken at my own risk/ peril.

I'm thinking about coupling a squirrel cage blower to a rider mower engine I have as a spare(on a chassis-can belt it) as a home-brew super-vac, and then removing it all that way(not sure where I can find large diameter rigid hose cheaply though)


04:15PM | 05/06/13
I hate this insulation. It works it's way down through the canister lights and causes hacking coughing and itchiness. My daughter is on no-stop medicines for the itch. I'm going to rip it out this summer and hopefully be done with it. This stuff is EVERYWHERE - in the walls, in the soffits, in the attic - ARGH

Also, whatever they used in my house is really sharp - tends to get in the skin and really hurt.

And yes, I'm sure it is rock wool - we had it tested during the home inspection


10:37AM | 03/17/15
Rockwool in the BATT form, instead of loose, has none of the problems the people on this page have listed.

Batt form is a rectangular block shape, when squeezed and fit into place it expands into the space between the joists (or between your rafters, if you are doing your attic ceiling) nicely filling air gaps (unlike delicate fiberglass batts, which often leave gaps). It doesn't fly around in the air like the loose stuff does. And it doesn't crumble over time.


07:36PM | 12/21/15
RE: alphanumeric2 breathing in all those fibers & becoming sick.

Listen up folks: there are all kinds of nasties within the walls of our houses. If you are tearing walls/ceilings open and NOT wearing even a rudimentary dust mask....well, brother, that's just dumb. Older house than 1987? AND no mask? That's stupid.

Keep and Wash your work clothes SEPARATE from house laundry. SEAL off all work areas from rest of house, if living/renovating in same house.

It's a new century, and we now know that "Industrial Disease" is the reason for your cancers/shortened lives.



08:22AM | 05/08/17
We went to have foam insulation added because we thought we didn't have anything in out outer walls, (best guess 1928/1932) They found rockwool and said they cant spray foam it because it would release a sulfur smell that can last 6 months +. Any idea of how we can insulate the house without tearing out all the plaster from the inside?


10:22AM | 11/22/17
I have rock wool in my 1900 house and my skin has had a rash ever since I've had exposure to it. I have two other friends that have had rashes from it as well. My rashes have not yet gone away. Hopefully once I am done with the improvements my skin will heal and not be a life long issue. I have been wearing pretty good masks, but I'd hate to think what this stuff does to your lungs. They still sell this insulation in the stores. Because of my skins reaction to rock wool I would never use it.


08:32AM | 01/30/18
boy ive been using rock wool for evory wall in my house. mice destroyed 75 percent of the insalation. never had the breathing problems tho tear out always used a respirator when pull the old rock wool out it does have alot of stinging fibers to it. but have had no such skin reactions. and the new stuff does have same stining fibers but it goes away in a day. ive installed over 30 bails of this no major problems. i think the respiratory issuse alot of people get are from what build up in the fibers over maney years rock wool acts as a really good fillter for air. and my case the old stuff i knew had sum really nasty stuff in it. mouse poop, dead mice and bats, bugs, all sorts of lovly. but the rock wool that still in the walls that havent demod yet. hasent degraded any after 60 plus years in the walls.


03:14PM | 05/07/18
I contracted to remove tile from an office space and found that the concrete floor had been leveled with close to 1/2" of mortar. Between the mortar and the concrete was a layer of rock/mineral wool, which had adhered to the concrete. The stuff is almost impossible to separate from the original floor. Does anyone know of a method of loosening the wool so it can be easily removed?


03:08PM | 09/11/18
Rockwool insulation muck like all installations has there hazards. Wear propper masks \ respirator, gloves, and safety goggles. One thing that is dangerous about living near the production facility.


11:42PM | 10/02/18
For anyone curious:
I am a professional contractor whose main focus is weatherization. I have literally dealt with every type of insulation in the industry. In my opinion, rockwool is hands down the most irritating material one can work with. Regardless of personal protective equipment worn, or safeguards observed, it's going to get on, and in you. Period. Government regulations are forcing us contractors to head in the rockwool direction due to its flame spread, and smoke resistance properties relative to fiberglass. However, I find it so repugnant that unless an alternative manufacturing process is developed, or regulations change, ill be turning the focus of my practice in another direction.


01:15AM | 01/21/21
I have Gold Bond Rock Wool in the attic for the ceiling insulation. It was put in during the mid 1950s. At first I was going to remove it but decided to keep it. I had to remove the paper that the batts came in. The paper shrunk after years and pulled the insulation away from the joists.
Putting my hand under the insulation during cold weather revealed just how warm the ceiling was.
Rock Wool is the best!


07:20PM | 07/18/21
GFBC> a lot of people will not take the shot and you will loose a lot of top people! if you force it Enjoy

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