Replies

1. 
   calvin | Nov 26, 2002 04:04am | #1

   It itches more, flies around just looking at it.  It's usually full of 50 yr old dirt, the paper vapor barrier falls off easily.  Many times it'll signal a rotten dirty timeconsuming bid busting job.  You might say I hate it.  Sorry, that's my only opinion from 30 years experience.

   You thinking of removing it so you can install one of the modern alternatives?

   __________________________________________

   Remodeling Contractor just outside the Glass City.

   http://www.quittintime.com/

1. 
   cocteau3 | Nov 26, 2002 04:52am | #3

   The stuff currently in the attic is loose. If it were ever in bats, they have decayed as you stated about the barrier. House is from the '20's, and inspector called it rock wool.

   sound correct?

1. 
   calvin | Nov 26, 2002 05:15am | #4

   check out Clouds link, I think I may be remembering as sometimes loose.  Most contact I've had with it is encapsulated in a kraft type paper, almost like batts.  However, just left a 20's house that had just a bit in the attic that was loose.  Similar to blown celulose but this stuff was definitely not that. 

   So, what are your thoughts?  Removal or what? 

   __________________________________________

   Remodeling Contractor just outside the Glass City.

   http://www.quittintime.com/

1. 
   CloudHidden | Nov 26, 2002 05:35am | #6

   I bought it the other year as ThermaGuard or something like that. It was in 2' x 4' x 4" batts. Don't recall it being itchy, but then I could work with fiberglass on a hot day w/o a shirt and not be bothered by it.

2. 
   cocteau3 | Nov 26, 2002 05:51am | #8

   Probably I would add blown in cellulose on top of it . . . or should I blow in fiberglass pink insulation? Or are batts best?

   I've heard of people using the dense pack cellulose as a loose fill attic insulation.

   j.

2. 
   4Lorn1 | Nov 26, 2002 05:48am | #7

   On the good side": It won't burn or support combustion like the binders, not the glass itself, will with fiberglass. It has, according to everything I have seen, the same insulation qualities as fiberglass. It is listed as having better sound absorption qualities than most, about as good as the purpose built acoustic fiberglass batts, fiberglass. Rodents and tradesmen, from what I observe, don't like to make nests in it as readily as fiberglass. Good to know if you have a tradesman infestation.

   On the down side: The fibers are stiffer, more likely to penetrate and itch than any but the earliest fiberglass. It often contains shards of mineral glass large enough to draw blood and have to be removed with tweezers. The best ones ever for the job:

   Uncle Bills TweezersThese have been customer favorites for years! 1 1/2" Silver Grippers, these are wonderful little tweezers. They are perfect for grabbing errant threads on your work, and picking out the cut threads in your Hardanger Embroidery work. The tips are super sharp, and the sides are strong heavy gauge stainless. They are very easy to grip and hold, and just the slightest pinch pressure gets you what you're trying to grab! Great for your first-aid kit, too, if you have a sliver! They come in the coolest little clear plastic tube, with a screw-off cover, too! Every stitching bag should have a pair! Uncle Bills Tweezers - $7.00:

   Available at:

   http://www.thesilverneedle.com/bestsellers.html

   A tool deserving of space in any tool box and first aid kit. My highest recommendation. I diverge so back to rockwool.

   Over time some of mineral wool brands, in some situations, can degrade into a mix of sharp fibers and very fine but abrasive dust that combines all of their possible bad sides and none of the finer points. The dust becomes airborne at the least touch and forms clouds that refuse to settle in a hot attic and make breathing akin to sucking razor blades. Woe to any who foolishly attempt to brush this from your eyes. Blink and suffer but do not touch. It also has an affinity for sweat and the nether regions of underwear.

   OK, you could wear a Tyvec suit and a respirator, get one with an exhaust valve, and goggles but these can make a 140 degree attic even hotter. After trying many variations I usually just go in without the gear and move as quickly as possible while trying not to disturb the stuff. Hosing, rinsing, off after a trip in the attic helps greatly but don't scrub. Have dry clothes standing by. Makes my skin itch and my eyes sting just thinking about it.

   On the up side mineral wool and the dust does seem to vacuum up easier than the longer strand fiberglass that can get caught in carpeting and such.

1. 
   calvin | Nov 26, 2002 05:57am | #9

   I write some #### little bs about rockwool and you turn it into a novel.  I very much enjoyed your version.  Thanks.__________________________________________

   Remodeling Contractor just outside the Glass City.

   http://www.quittintime.com/

1. 
   ReinTaul | Nov 26, 2002 06:43am | #10

   There is a commercial version sold in these parts called Roxol. It is somehow made from volcanic strands (?).

   My experience with it has been as an acoustic insulator. It is fantastic for that. Probably because is is denser.

   I have never worked with it for thermal purposes. They promote it as an exact replacement for fiberglass. I'd be interested in hearing from those who have tried it that way.

   I did not notice any extra irritation, but then again, I have thick skin. ;-)

2. 
   TrimButcher | Nov 27, 2002 03:32am | #11

   Roxul is better than fibreglass, IMHFO.  Cuts nicely (Lee Valley sells a serrated bread knife for this; I use my OLFA with the blade sticking way out) for a good friction fit (don't cram it just like you don't cram fibreglass else you lose the R value).  Doesn't choke my throat/needle my skin as bad as fibreglass.  The mice/chipmunks/squirrels don't make nests in it, whereas they love fibreglass.  Doesn't seem to get water-damaged as easily as fibreglass, but that's my observation.

   I think Roxul is related to rockwool or mineral wool, but has better binders/quality.  We put paper-covered mineral wool insulation batts in my childhood cottage in the 70's.  I'm still itching and coughing...

   From a thermal standpoint, it's at least a match for fibreglass. 

   Regards,

   Tim Ruttan

3. 
   MajorWool | Nov 27, 2002 05:49am | #14

   Well, on Sunday I sucked out another 8-9 contractor bags of the stuff with my improvised insulation remover. I now have the south side attic completely free of rock wool up to where the 3rd floor toe-wall and floor start. The first load of 10 bags weighed 380 lbs, so I'm figuring just over 300 lbs for this last batch. The attic dimensions were 11x28 ft, so we are looking at around 300 sq ft, or from 2 1/4- 2 1/2 lbs/sq ft, and the depth was from 4-6 inches, so my guesstimate of 6-8 lbs/cu ft was pretty close. This of course wasn't just the rock wool, but also probably 60-90 years of roofing jobs, dust, dirt, and debris.

   I replaced it with a mixture of faced r19/21 fiberglass in between the full dim 2x6 joists. We can already feel the difference downstairs as the rooms stay warmer longer after the heat goes off. My current plan is to build a 16" wide catwalk on 2x4's along the toe walk for infrastructure work, insulate further with r13 under the catwalk, and then layout unfaced r19 batts over the rest. What a difference in appearance. I can hardly believe it is the same attic I started on a year ago. My first discovery after cutting an access door through the toe wall was about 300 sq ft of old carpet loosely rolled up. yech!

   I've also decided to go ahead and do as much of the north attic this weekend as I can, and then remove the dust collector system out to the garage. I figure that once Boingo makes his appearance around Jan 1, that DC will never see the inside of the house again, so best to do it now.

   My basic uniform is either a long sleeve T or sweatshirt, mid forearm length heavy rubber gloves, jeans (all washed separately), some "bouffant" caps I kept from the OR, and a wilson rubber mask with HEPA cartridges. I wore the mask for 4 hrs on Sunday, didn't sneeze, and my snot was clear so that was a good sign that the mask was doing its job. I also run a jet AFS 1000 in the room where I access the attic to pick up any stray airborn materials, and run the attic ventilation system to apply a negative pressure at the access door. I figure that once this is done I'll steam the carpets on the 2nd and 3rd floors to lift up any settled construction debris. I did find a tuft of gray material on the second floor, but it was just a wad of cat hair, so I've been able to contain 99.99% of the material by transporting it in the metal trash can.

   I thought about just adding more cellulose on top, but now I'm really glad that I put in the effort to really do it right, that is, remove the old stuff completely. I'm sure there will be some debate about my choice of using fiberglass. If it were a different season and I had a larger block of time to do it, then I would have gone with cellulose, but as it was, most of this work was done one or two joist bays at a time, and it was much easier to stick in a few batts of glass to reinsulate immediately.

2. 
   CloudHidden | Nov 26, 2002 04:06am | #2

   It's actually strands with a wool-like feel made by smelting ore and spinning it into fibers. Feels not a whole lot different from fiberglass, but denser. Harder to cut or separate. Because of its origins, can be used as a fire stop. That's my familiarity with it.

   http://www.amerrock.com/american.htm

3. 
   MarkH128 | Nov 26, 2002 05:33am | #5

   Rock wool is heavy. It looks like fiberglass somewhat though.

1. 
   Piffin | Nov 27, 2002 05:01am | #12

   "Rock wool is heavy. It looks like fiberglass somewhat though."

   Yeah, kind of like fibreglass that has been soaked for a year in the grey water from the septic tank and then dryed with a torch.

   Excellence is its own reward!

   "The first rule is to keep an untroubled spirit.

   The second is to look things in the face and know them for what they are."

   --Marcus Aurelius

1. 
   MarkH128 | Nov 27, 2002 05:06am | #13

   Yeah, like that.