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Why no rockwool insulation?

ForceFed70

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In Canada, fiberglass bats are quickly becoming a dead product. Only thing keeping them around is that they are slightly cheaper than rockwool. Most construction now is rockwool and it's to the point where it's assumed rockwool will be used.

From garage builds on this forum and discussions here, it's apparent that's not the case in the US.

Does anyone know why? Is it because rockwool is a Canadian invention and slower to be adopted in the US as a result?

My understanding is that rockwool is superior or "as good" as fiberglass in just about every manner except perhaps with regard to weight and material packaging (fiberglass bats compress better and weigh less).
 
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GLTHFJ60

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My understanding is that rockwool is a superior insulating material, but a bit more expensive. The cost is likely what's slowing adoption, even if the difference is negligible.

I don't see rockwool carried in stores like home depot or lowes in the US, at least not in my region.
 

matt_i

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From my reading its a greater R-value per inch and also more reliable R-value because of the rigidity of the product. I plan to use it in my sidewalls.
 
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ForceFed70

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Here it's in all the home improvement stores. It's getting easier to find rockwool than fiberglass. When I compared a couple of months ago, fiberglass was about 10% cheaper.
 

ocanuck

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I'm also in BC and Rockwool was 50% more expensive at my cost than FG. The markup on FG is huge, so consumers see a small price difference at Home Depot but for builders who aren't paying listed prices, the difference is actually much much bigger.

Needless to say, I went fiberglass for my shop... R20 in the walls, R12 and R28 in the attic. FG batts were $7 more expensive than going cellulose in the ceiling, and now I dont have deal with the mess.
 

Toomanytools?

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I think it's just getting geared up here in the US. Some of the major companies are just acquiring the rights to market share. It seems to outperform fiberglass in everyway so just a matter of time until we see it more widely used here.
 

Movover

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We have it here I have been using it in all my walls as I have been redoing rooms, Love the firedampening/noise properties most of all
 

Modern Jess

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I used it in my workshop build, and really loved working with it. Easier to cut and shape to fit in odd nooks and crannies, and really fill those areas properly. Yes, definitely more expensive -- I used Roxul -- but I would do it again in a heartbeat. Actually, there were parts of my shop where I left the old fiberglass intact, and now I wish I had replaced it all with Roxul for a higher R value.
 

Fixin'Stuff

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Roxul has slightly higher R-value for a given space, but the price premium is rather painful. Roxul is shown here at 98 cents per square foot: http://www.lowes.com/pd/Roxul-Wood-...th-Sound-Barrier-15-25-in-W-x-47-in-L/3388304 (Local price: $58.90 for 59.7 SF) Plus, it is unfaced so we have to add in the cost of adding a vapor barrier.

While R-13 Fiberglas is at 47 cents per square foot: http://www.lowes.com/pd/Johns-Manvi...-with-Sound-Barrier-15-in-W-x-32-ft-L/3032423 (Local price: $49.98 for 106.56 SF) Comes with vapor barrier.

Unless you live in a VERY cold climate, it would take a lot of years for it to pay for itself.
 

Modern Jess

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Nothing in my shop was chosen based on ROI. Instead, I optimized for effectiveness, labor savings (sometimes on the front end, sometimes on the back end) or just what I was interested in at the time. I liked working with Roxul much better, and it was more effective and easier to fill all the voids. So a win/win, in my book.

Also, no vapor barrier needed in my climate.
 
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ForceFed70

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Plus, it is unfaced so we have to add in the cost of adding a vapor barrier.....
(Local price: $49.98 for 106.56 SF) Comes with vapor barrier.

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.
 

jives

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I just bought kraft FG on sale for 0.40 sq foot. . . Roxul was over twice the cost. Would love mineral as it is clearly a better product. But not $700 better.
 

jeff_gates

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We bought rockwool for the shop, we bought 9 pallets from home depot delivered for about $5,200 FG was a little cheaper but not by much.
 

ItsNemo

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There's more than just increased R value that you get with Roxul though over FG. Things like it's fire protection, the fact that it won't promote mold growth or hold water, it deadens noise better, won't sink or sag in the joists over time, is easier to work with and install...all around it's a superior product which makes the price even more worth while.
 

Boilerhouse

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Last I compared rockwool to fiberglass, (some years ago admittedly) the rockwool was actually slightly cheaper, had better R value and as mentioned was a better fire and noise retardant. However, I found rockwool is not a very robust product. Each time its handled there is a tendency for the batts to crumble. Fiberglass is superior in that regard.
 

mjwelte

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Also look for a local retailer other than Lowes or HD. I found a place 30 miles east of town that was almost half the price the big box stores. They were also much easier to deal with. We used it and will never go back to fiberglass. It was about 10% more expensive but the sound insulation more than made up for it.

Mark
 

DC73

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Also look for a local retailer other than Lowes or HD.

Agreed. Ask around. I did my entire workshop with a layer of Roxul and couldn't be more pleased. While I found it at Lowe's, I contacted 84 Lumber and they ordered it for me at a much better price.

For the ceiling, I ended up with one layer of Roxul and one layer of fiberglass. I hadn't intended to do that but got a hell of deal on some unfaced R19 fiberglass batts. So, I put the Roxul down first for fire protection, sound proofing, and to control airflow through the joist cavity and then topped the Roxul with the layer of fiberglass. Works very well for my climate

DC
 
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CNGsaves

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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.
 

LS6 Tommy

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Citation?

I suspect you're probably thinking of vermiculite.

No citation needed. Common knowledge. Rockwool brand insualtion. Asbestos. Period. Not every product they make, but a LOT of the older ones, up until the late 80's. The stuff having the same name that is made by Delta now is safe.

Tommy
 
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Modern Jess

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Nope. Rockwool brand insualtion. Asbestos. Period. Not every product they make, but a LOT of the older ones, up until the late 80's.

Again, can you provide a citation? Some quick googling reveals no such link, with a number of sources actually specifically stating that there is no link between rockwool and asbestos. The only even remote suggestion I could find is on a home inspectors forum, with one guy claiming that there is a link, and a bunch of other inspectors basically telling him he's on crack.

The only even vague connection is that the Gold Bond company bought the "Rock Wool" name, and Gold Bond also at some point produced asbestos-containing products. But not rockwool.

So I'd love to see a credible source on this subject.
 

LS6 Tommy

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Modern Jess

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I've been dealing with the abatement of Rockwool's stuff literally for decades

There's rockwool the material, and then there's the Rock Wool Manufacturing Company.

From your citation:

"Rock Wool manufactured asbestos insulation and other asbestos-containing products for a variety of purposes. Their pipe insulation products are likely responsible for much of their ties to asbestos exposure. These products were used in many locations and affected a number of occupations, including power plant workers, shipyard workers and even Navy crew members. Rock Wool products were commonly used in shipbuilding."

Again, do you have a source that indicates that rockwool -- the material -- contains asbestos?
 

Strouty

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Tommy did you even read the link you posted?

Direct quote:

Two products manufactured by Rock Wool known to contain asbestos include One Shot and Delta Maid AF. Both of these items are insulation cement products and were likely used to help secure pipe insulation.

I guess I read much slower!
 

theoldwizard1

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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.

If we are talking vapor barrier, I am a big believer in ZIP System exterior sheating. Cuts and installs like plywood/OSB, tape joints (should be faster thna applying a house wrap) and you are done !
 

coldh2o

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There's rockwool the material, and then there's the Rock Wool Manufacturing Company.

From your citation:

"Rock Wool manufactured asbestos insulation and other asbestos-containing products for a variety of purposes. Their pipe insulation products are likely responsible for much of their ties to asbestos exposure. These products were used in many locations and affected a number of occupations, including power plant workers, shipyard workers and even Navy crew members. Rock Wool products were commonly used in shipbuilding."

Again, do you have a source that indicates that rockwool -- the material -- contains asbestos?

This^^^ There is no history asbestos was ever used in batt insulation. Vermiculite, pipe wrap, etc. but not batts. Mineral wool or rock wool does not contin asbestos.
 

Hornman

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If we are talking vapor barrier, I am a big believer in ZIP System exterior sheating. Cuts and installs like plywood/OSB, tape joints (should be faster thna applying a house wrap) and you are done !

I too like the Zip system, it is a very good housewrap product. But, it is not a vapor barrier. The Zip systems data sheets talk about "optimum breathability" to keep free water out of the wall and allow the wall to breathe. A vapor barrier Is impermiable and usually goes inside, thus the talk about PE sheeting.
 

slip knot

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The Habitat house I helped out on a few weeks ago was using some kind of unfaced wool type batts. I didn't get to look at the packaging but really liked how dense they were. seemed like they would stay put for the long haul.

A lot of my rentals have fiberglass batts and they've all settled over the years.
 

LS6 Tommy

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Tommy did you even read the link you posted?

Direct quote:

Two products manufactured by Rock Wool known to contain asbestos include One Shot and Delta Maid AF. Both of these items are insulation cement products and were likely used to help secure pipe insulation.

I guess I read much slower!


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
 
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NUTTSGT

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When stuff costs more, it seems harder for the usage to take hold. Around here, spray foam is finally taking hold and there are a couple of spray foam contractors now.

I have seen rockwool at my local HD, but not really checked it out for size of batts/R-value or price.
 

Gerald O

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Roxul Comfortbatt rock wool for 3.5" depth wall cavity is rated R15. Home depot is selling this at about $0.88/sqft. This is unfaced and requires an additional vapor barrier at added cost.

Owens Corning 3.5" R15 kraft faced fiberglass sells for $0.76/sqft and requires no additional vapor barrier for much of the US.

So, no insulation thermal performance advantage for the rock wool and higher cost. There's your answer for why it is not more popular here.
 
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Falcon67

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We had that **** in our old house and frankly, I don't care for it. Collects dirt, dust, mice hide in it, it packs down to nothing over many years and it a PITA to work around. Since that house was built in 1926 and placed in town in the 50s, I've probably got a snoot full of asbestos. I covered all of it with 6" unfaced batts - made a huge difference in performance.
 

Modern Jess

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We had that **** in our old house and frankly, I don't care for it. Collects dirt, dust, mice hide in it, it packs down to nothing over many years and it a PITA to work around.

You've just described fiberglass. Especially with mice -- mice love using fiberglass as nesting material.

Or maybe we're just talking about different products. Modern rock wool is in bat form, wedges itself between studs, and does not pack down over time.
 
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