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Why no rockwool insulation?

Falcon67

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No, it was rockwool. Very likely placed back in the 50s, early 60s. A sea of gray dust bunny looking junk, only about 2" thick by the 1990s. I considered sucking it all out but eventually passed on that large a project.
 
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ItsNemo

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That sounds like blown in cellulose...you couldn't **** rockwool insulation out with even the most powerful of vacuums.
 

Angelfire

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USA is lazy and cheap. Faced fiberglass gives the illusion that wall has actually been insulated and vapor barrier added . . . nope.

Canada is actually Doing It Right with the Rockwool and true vapor barrier.

Eventually USA will catch on, but don't count it too soon with low petroleum/NG costs right now.

Europe has it figured out as well.....I didn't see any fiberglass in the supply stores while living in Ireland, just mineral wool. When I did an addition on my home (in the US), I did the research and came to the conclusion that although more expensive, the rock wool was a superior product. So bit the bullet and used it and I'm glad I did. The rest of the house was done in fiberglass when it was built and you can definitely tell the difference between the addition I did and the original house. Love the sound deadening we get with the rock wool. Actually had an acquaintance drop by the addition when I was building. This guy sells/installs insulation for a living. He was utterly flabbergasted when I told him I was installing Roxul.....kept saying it was an industrial product and not used in homes. I held my ground and installed the Roxul, but it shows the reach of the "pink" **** in terms of marketing etc....If Roxul (or CertainTeed) did more to advertise the stuff, it might improve sales thereby lowering the price.
Cheers.
 

Rock knocker

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Is it because rockwool is a Canadian invention......

No. ........

Slag wool was first made in 1840 in Wales by Edward Parry, "but no effort appears to have been made to confine the wool after production; consequently it floated about the works with the slightest breeze, and became so injurious to the men that the process had to be abandoned". A method of making mineral wool was patented in the United States in 1870 by John Player and first produced commercially in 1871 at Georgsmarienhütte in Osnabrück Germany. The process involved blowing a strong stream of steam of air across a falling flow of liquid iron slag which was similar to the natural occurrence of fine strands of volcanic slag from Kilauea called Pele's hair created by strong winds blowing apart the slag during an eruption
 

aptdweller

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I think the simplest answer is cost. Home builders are going to use whatever is cheapest to maximize their profit.

When it comes to DIY and pro home renovations, most people are using Roxul, mainly for ease of use. I certainly wouldn't buy fiberglass again.

Just as a data point: Roxul is 86 cents a ft2 and fiberglass is 45 cents at ft2 where I am.
 

csp

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If we are talking vapor barrier, I am a big believer in ZIP System exterior sheating.

Vapor barrier faces the conditioned space, it doesn't go on the outside of the building. ZIP is a water resistant air barrier, not to be confused with an interior vapor barrier.
 

paranoid56

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So, in conclusion: These are the reasons that rockwool hasn't caught on in the US:

- Cost.
- Lack of vapor barrier (though you probably don't actually need it).
- Americans don't know what the @#$% rockwool is.

cost is the big one. people are dumb.

when i redid a room (no insulation in any walls) i went to buy some but couldnt locate any in my town at the time. I saw that i could order it from HD but would be 2 weeks. I didnt think my project out enough and figured i could just get it on the day i needed it. so crappy pink stuff went in.

next time i demo a room though i will be preordering some.
 

sammer

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Fernie, B.C.
I did Roxul in my shop.
As a demonstration to my buddies I put the propane torch to it until it glowed red. It left a slight mark in the batt. Then I put the torch to a batt of fiberglass it burned clean thru and we all had to vacate the shop from the fumes.
It's heavy and dense. It cuts easily and precisely with a bread knife. Easy to cut around boxes, wiring and pipe. The metal in it will dull your knife so buy a couple at the dollar store.
It will give you a bit of an itch but nowhere nearly as bad as fiberglass.
The extra money was worth the ease of installation, and the knowledge that I have an extra fire break if it ever comes to that.
The only thing that I didn't like was if you kneel on a batt it compresses and doesn't spring back.
I'm not surprised it's not more popular in the states, I think roxul only got a US distributor around 2012. I think as more people use it, it's popularity will grow.

sam
 
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ForceFed70

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No. ........

Ah, but who actually came up with the idea of using Rock wool as insulation?

I also found another interesting fact.

Roxul has had a plant in Canada since 1999. 1st plant in the US Didn't open until 2014. Prior to 2014 all of the Roxul Insulation (does anyone else actually make Rock Wool Insulation?) in the US came from Canada.
 

nc416

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I have used roxul insulation. I hate it. if you have to remove it and re-install it , good luck, it breaks apart and is a pain.

I did a whole house using this product
http://www.knaufinsulation.ca

Worked amazing, not itchy. It felt to me it was a hybrid and it cut realy nice and did not break apart like roxul, and it was cheaper than pink and roxul.

and from their website :

Microbial Growth (ASTM C 1338)

Does not support microbial growth or attract insects or vermin. In addition to being classified as mold resistant by GREENGUAR
 
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ForceFed70

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I've heard the handling argument a number of times and it interests me.

Yes, it certainly "breaks down" with rough handling. You can't fold a batt in 1/2 like you can FG. But I haven't found it to be a problem and I've used Roxul for numerous projects. You make it sound like the stuff crumbles in your hands before you can get it into the walls.

You do need to be gentler with it. But I'm confident I could remove and re-install the product (with care) if I needed to.

But moreso - why is this even a concern? Are you guys frequently pulling out all of your insulation and then re-installing it. Reusing insulation is like reusing 2x4's... the pro's throw it in the garbage as it's not worth their time. Only people reusing the stuff are cheap old men with way more time than money. Okay you got me - that sounds like GJ members :lol_hitti
 

beakie

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No, you don't need to read slower, I need to think more clearly. Those types of materials made by Rock Wool are EXACTLY what I have dealt with. Apparently I was not in a clear mental state last night. I never made it clear which products I was referring to. I went off on a tangent from the original subject and I'm the one who is wrong here.

Sorry, guys!!

Tommy

I'm all for the Roxul, it's all I use/will use, and for all the positive reasons given.

but, more importantly.

the quoted post above, may be one of the bests posts I've ever read... on the whole interweb!

someone on the internet;
acknowledged their error,
admitted their mistake,
provided an apology.

kudo's to Tommy.
 

TractorJeff

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Elkhorn, WI
We switched to it at work. Interesting stuff! The guys stuff the standing walls now, instead of a separate department that used to lay the wall panels down to install commercial grade fiberglass and sheetrock. Enclosure walls are now assembled twice as fast!
 

2CWG

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SoCal
Ah, but who actually came up with the idea of using Rock wool as insulation?

I also found another interesting fact.

Roxul has had a plant in Canada since 1999. 1st plant in the US Didn't open until 2014. Prior to 2014 all of the Roxul Insulation (does anyone else actually make Rock Wool Insulation?) in the US came from Canada.


"Thermafiber, Inc. is proud to announce that June 6th, 2009 is the company's 75th Anniversary. Founded as American Rock Wool in 1934"

Not saying they were the first, just saying that Rock Wool as insulation isn't a "new" thing here in the US. The insulation they produced was utilized primarily in industrial and military applications though, for what that's worth
 

Crazyjake8493

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Upstate NY
Easy to find Roxul at the big stores here, just a little more expensive. I don't buy fiberglass anymore, everything I've done in the house is rock wool. The garage is a mix of fiberglass and rock wool, due to getting a bunch of fiberglass rolls/batts for free.
 

JMURiz

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I use Roxul now that I can get it locally, I love working with it. All you need is a long bread knife and some gloves. Fit's the spaces very well too.

Hated dealing with f'glass when doing my garage, now I'm glad I don't have to on future projects.
 
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texasprd

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San Antonio, TX
No, it was rockwool. Very likely placed back in the 50s, early 60s. A sea of gray dust bunny looking junk, only about 2" thick by the 1990s. I considered sucking it all out but eventually passed on that large a project.

This sounds like the stuff in my parents' house (built in '40s?) and in part of the attic of my house (built in '97). Looks like dirty grey blown-in fiberglass, leaves stuff on your hands if you touch it (ad I think it falls apart, but cant remember offhand). It that's not rock wool, what is it? And if it is rock wool, why would I want to use it again when its so nasty and settles like Falcon pointed out? Is this "old style" rock wool?
 

Jess

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Oct 22, 2006
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Vancouver Island, BC Canada
The old rockwool loose poured or paper faced batts have been around for a long time. I have a house built in 1947 that was insulated with paper faced in the walls and loose poured into the attic. During renos, we replaced the stuff in the exterior walls with Roxul batts and blown in Attic Cat on top of the stuff in the attic. In order to dispose of the old rockwool batts, we had to have testing done for asbestos. Came back zero but some brands may have had it. This place was also drywalled with 3/8 thick drywall and not taped. Spent a lot of time screwing the sheets, taping and then having a knockdown that hides all the sins. My current home, built in 1990 has loose poured mineral wool and I plan to have it vacuumed out and replaced. Its dusty and inadequate for my needs. The Roxul products are nothing like the old stuff, just like even fibreglass batts have changed over the last 40 years to be a lot nicer to work with.
 

Fueler

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Urbana, IL
Roxul fan here despite the itch factor. Long sleeves and buttoned up shirt helps. Still better than fiberglass.

I just remodeled a wall in the shop and used it. Pole barn. This wall faces the highway. Amazingly dead quiet now. Used to be able to tell when the UPS truck was arriving. No more.

I have been putting it in the home attic a bit at a time. I pick up 2 or 3 units at Home Depot every now and then and install.
The old 50s insulation was flat as a pancake. Since I started at one end of the house there is a noticeable difference in one end of the house to the other. Might actually get it done when it gets cooler.

Why not do the attic all at once and get it over with? Certainly should but in small doses it doesn't hurt as much financially and I don't dread going up there for an extended time.

My son is doing his home garage with it a bit at a time.
FYI - one unit at about $50.00 will fill 6 wall cavities.
 

csp

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And May I add! Its got to be the Worst stuff to work with or be around it!

Well you did add that. However, it's hard to give your statement any credibility without any kind of explanation.:dunno:

I love working with it and do so whenever possible vs fiberglass, especially when sound is a factor to consider.
 

Astro-t

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Since its otherwise known as rotten cotton! Its fiberglass! It just seems to be all over the place when its installed!
 

Modern Jess

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This sounds like the stuff in my parents' house (built in '40s?) and in part of the attic of my house (built in '97). Looks like dirty grey blown-in fiberglass, leaves stuff on your hands if you touch it (ad I think it falls apart, but cant remember offhand). It that's not rock wool, what is it? And if it is rock wool, why would I want to use it again when its so nasty and settles like Falcon pointed out? Is this "old style" rock wool?

Because that's not modern rockwool insulation. Modern rockwool doesn't settle, and the bats are solid slabs that you cut with a knife and wedge between the studs.
 

csp

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Since its otherwise known as rotten cotton! Its fiberglass! It just seems to be all over the place when its installed!

So are you talking about rock wool or fiberglass? Your train of thought is REALLY hard to figure out.:dunno:
 

Pack Rat

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I'm prepping an exterior wall for window and door replacement. I pulled off the rotted wood siding
and the old celotex sheathing. Guess what, no insulation. I'm using Roxul and installing it from
the outside and then sheathing over it.I love the stuff. It has a gentle learning curve.
The videos on the Roxul sight is a big help. You have to be careful handling it and if you use a large
putty knife around the edges you can pull it out to make it nice and flush with the face of the studs.
I wore a tee shirt, cotton gloves, and a dust mask, and had no issues with itching or breathing.
Fine Homebuilding had an article on mineral wool insulation in the Nov. 2015 issue, you can read it online.
 

dutchgray

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The only place you might use it here in a new build is in the wall cavity, you can't get enough thickness anywhere else to be compliant now. We use 150mm of the foam board in the roof often with the multi layer foil stuff as well, up to 100mm of foam board in the walls and recently 300mm of floor grade polystyrene under the ground floor. It would be nice to get away with so little insulation.
 

csp

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You keep giving 1/2 information about why you don't like rockwool, assuming everyone else knows what you're talking about.

How about taking a minute and spell it out as if nobody has any idea what it is you're referring to?

Just one example:
Astro-t said:
Rock wool is fiberglass? Do you know what's in it?

Were you actually asking if rock wool is fiberglass or making some sort of hidden/vague inference?

Do you know what's in it? If you do and whatever is in it is what makes you not like it, just say what it is! Is it really that hard to figure out?
 

Astro-t

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It's known in the business as rotten cotton! And as stated in the post its fiberglass! My opinion is its just nasty stuff to be around.
 

jeff_gates

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Olalla, WA
Ah! Perhaps this is part of the reason.

In Canada they have stricter building codes regarding vapor barrier. Backed bats are not good enough, you must use a dedicated barrier. Everyone uses poly plastic and tuck tape for the barrier tho there are other options. Backed insulation is considered specialty use.
In Washington we started to rock wool the walls R21, then we put up the vapor barrier and our framer told us that they stopped putting up vapor barrier. We called the building department, and the also said the same. They were seeing more mold issue with the vapor barrier.

and the cost of rock wool was not that much more then fiber glass by the pallet, and I got 9 pallets just over 5K delivered.
 

Pack Rat

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I find building science a fascinating subject. New materials and methods are developed to address old
problems. I especially like seeing the methods used in other parts of the world.
 

Modern Jess

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It's known in the business as rotten cotton! And as stated in the post its fiberglass! My opinion is its just nasty stuff to be around.

First, please quote so we know who you are responding to.

Second, I don't give a **** what the fiberglass reps call it. Their opinion is driven by their paycheck, not what's right.

Third, you have no freaking idea what you're talking about. Rock wool is NOT fiberglass. You are entitled to your own opinions, but you aren't entitled to your own facts.
 
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