Fiberglass insulation is junk?

[gogolf0401]

So my cousin was telling me recently that he heard that fiberglass insulation was junk. He said that recent research has found that the previous idea of how it would provide an R-value was wrong. He heard this from a professor at Kaplan. I guess the teach is on the state board that sets construction standards and practices. He says they've done numerous studies.

Has anyone else heard anything like this?

 

[James-W]

That's news to me. I have fiberglass insulation in the house and in the garage and it is working just fine for me.

 

[Shiftless]

Me too ^^^^

 

[Dick in Wisconsin]

Does the teacher suggest an alternative to something that has been used for what ... 60 years with apparent great success?

If it fiberglass insulation didn't work, I would think by now everyone would be pulling it out and replacing it with rolled up newspapers.

"Kaplan" ... is that the for-profit Kaplan University?

 

[383 240z]

News flash, all universities are for profit.

 

[gogolf0401]

Why would it matter if this came from a teach at a university? It's not like they're selling insulation.
He didn't say that it doesn't do anything, but that the R-value does not meet it's apparent rating. He said it is about the same as a thin sheet of closed cell foam. He doesn't remember how thin, but 1-2" maybe.

 

[RM209]

That's news to Warren Buffett as well. He's owned a very large stake in Johns Mansville fiberglass insulation for many years. He normally doesn't invest in junk.

Perhaps he never met your cousin.

RM209

 

[gogolf0401]

I'm obviously skeptical otherwise I would have not posed the question on this forum.. I was just curious if anyone else has heard such a claim or has any comparison stories which would debunk or otherwise promote this theory.

 

[rburke65]

So the alternative is.......?

 

[NUTTSGT]

The same professor probably says that cellulose insulation won't burn either.

 

[larry_g]

Your going to have to cite the whole document or speech to have any meaning. I'm sure in any test someone can prove that something is better than something else just by how the test is set up and the results interpreted. No news there...

lg
no neat sig line

 

[finn]

News flash, all universities are for profit.

False

 

[DEnd]

The "professor" is both right and wrong. Properly installed Fiberglass performs to its rated R-value (this does not mean the wall assembly performs at the R-value of the insulation). The problem with fiberglass insulation is that in batt form it is hardly ever installed properly. Also of note is that fiberglass performs better at low temperatures than at high temperatures, in actuality however most insulations do this.

http://www.greenbuildingadvisor.com/blogs/dept/musings/installing-fiberglass-right

 

[James-W]

You could say the same thing about ANY insulation, if it wasn't installed correctly it isn't very good.

 

[Norcal]

There was someone saying that fiberglass insulation was going to be the next asbestos, still waiting on that one, but not holding my breath, would have expired years ago had I done so.

 

[zmaxmotorsports]

There was someone saying that fiberglass insulation was going to be the next asbestos, still waiting on that one, but not holding my breath, would have expired years ago had I done so.

 

[Spudland_Dave]

The problem with fiberglass insulation is that in batt form it is hardly ever installed properly.

Anytime you pay someone else to do something for you...you'll get a sloppy job. Period. I've seen it...

 

[coldh2o]

That's news to Warren Buffett as well. He's owned a very large stake in Johns Mansville fiberglass insulation for many years. He normally doesn't invest in junk.

Perhaps he never met your cousin.

RM209

I'm very skeptical about the "fibreglass insulation doesn't work" suggestion also, but this statement makes no sense at all to me. Do you think Buffett really cares about the technical performance, or the financial performance?

 

[RM209]

I'm very skeptical about the "fibreglass insulation doesn't work" suggestion also, but this statement makes no sense at all to me. Do you think Buffett really cares about the technical performance, or the financial performance?

My point is that Warren Buffett doesn't make a habit in investing in industries or technologies that don't work, and he invests for the long term; very often for over 20 years. He's known for thoroughly researching his investments, and if he believed the companies didn't didn't deliver on their fundemental value proposition, he wouldn't hold large positions in those companies. That's why he passed on so many companies from the "dot.com" bubble of 2000, and as a result never got burned when they collapsed.

RM209

 

[buddyboy]

junk is a relative term, one mans junk is another mans treasure.

warm beer is junk compared to cold beer

warm beer is gold compared to no beer

sometimes in order to get a student to think you have to make outrageous statements, this professor not only has this student discussing it, but his cousin and 1/2 a dozen people on this forum.

this professor will probably ask the class if using black iron pipe for airlines is a waste of time and money when pvc is so cheap and easy to work with

 

[DC73]

So my cousin was telling me recently that he heard that fiberglass insulation was junk.

The problem discovered with fiberglass insulation is that the effective r-value of the entire wall assembly can be much less than other insulation products depending on the details of construction and how well the fiberglass was installed.

Fiberglass insulation allows air movement through it much easier than other forms of insulation. If wall cavities are not sealed tight enough to avoid this air movement the overall r-value of the wall assembly is degraded. You also do not want to compress fiberglass insulation.

Bottom line is that fiberglass can work but sloppy installation and lack of attention to proper detail will reduce it's effective r-value. It's hard to get fiberglass "right".

So the alternative is.......?

I like mineral wool. Sound resistant, fire resistant, blocks air movement and has a higher r-value per inch than standard fiberglass. The cost is a little higher but worth it in my opinion. Mineral wool is not as costly as spray foam.

Blown-in cellulose in the attic is also a better alternative than fiberglass and is fairly inexpensive, especially if you rent the machine and do it yourself.

Both closed cell spray foam and open cell spray foam are superior to fiberglass for many reasons but at a much higher cost.

The "professor" is both right and wrong. Properly installed Fiberglass performs to its rated R-value (this does not mean the wall assembly performs at the R-value of the insulation). The problem with fiberglass insulation is that in batt form it is hardly ever installed properly. Also of note is that fiberglass performs better at low temperatures than at high temperatures, in actuality however most insulations do this.

http://www.greenbuildingadvisor.com/blogs/dept/musings/installing-fiberglass-right

Good article. There are others on GBA that explain the differences in various insulation products.

DC

 

[Falcon67]

Just points out that an insulated wall is a system and should be treated as such. I cheesed out and didn't caulk the wall cavites in my shop before adding insulation - I know it's going to be somewhat less effective because of it. However, I did take the time to make sure batts were snug and cut to fit around any obstacles. I used R-13 batts in the already covered ceiling - I could tell they made a difference going in. After caulking the ceiling joints, it about doubled the "feel" of the insulation performance.

 

[DEnd]

You could say the same thing about ANY insulation, if it wasn't installed correctly it isn't very good.

That's true. Spray foam insulation is also susceptible to installation errors. The issue with Fiberglass Batts is that installation errors are very wide spread. It can relatively easily be installed correctly, but finding subs who will actually do that the first time is a tricky proposition. Insulation subs often don't do the quality assurance and quality control that is needed with fiberglass batts, though that is changing.

Anytime you pay someone else to do something for you...you'll get a sloppy job. Period. I've seen it...

And That's why my Miata is so unreliable... Oh wait no it's not. The trick is to learn what quality is and to seek it out. That's why I reference Building Science Corporation, Energy Vanguard, Green Building Advisor, and others so often on here. Those companies not only seek out what quality is but they also will teach you what to look for, often they give this information away.

I'm very skeptical about the "fibreglass insulation doesn't work" suggestion also, but this statement makes no sense at all to me. Do you think Buffett really cares about the technical performance, or the financial performance?

Buffett is very concerned about technical performance. Technical performance is part of what Buffett calls a company's economic moat. It's partly why he bought BNSF.

 

[LaneRover]

My 2 cents . . .
I believe that one of the issues is how easily fiberglass insulation gets installed improperly. If it is compressed it no longer has it's same r-value.

I just re did our family room and was amazed how many gaps were present because wiring pushed the insulation out of the way or where the insulation was just pushed behind wiring or pipes - thus little to no r-value.

So far I am pretty impressed with using the mineral wool insulation, so I think I know why DC73 likes it. It doesn't compress nearly as easily or get pushed out of the way as easily.

Did I replace ALL of the fiberglass insulation? Replacing all wouldn't be cost or efficiency effective at all. I did replace it around wires and where the fiberglass had been pushed out of the way or where it looked like at some point there had been a dampness issue. It's my understanding that the mineral wool doesn't soak up water the way Fiberglass does and that vermin tend not to like it either.

 

[Squankum]

That's true. Spray foam insulation is also susceptible to installation errors. The issue with Fiberglass Batts is that installation errors are very wide spread. It can relatively easily be installed correctly, but finding subs who will actually do that the first time is a tricky proposition. Insulation subs often don't do the quality assurance and quality control that is needed with fiberglass batts, though that is changing.

And That's why my Miata is so unreliable... Oh wait no it's not. .

I've got it! We need more Japanese construction workers!



I'll run away now.



.

 

[RM209]

My 2 cents . . .


Did I replace ALL of the fiberglass insulation? Replacing all wouldn't be cost or efficiency effective at all. I did replace it around wires and where the fiberglass had been pushed out of the way or where it looked like at some point there had been a dampness issue. It's my understanding that the mineral wool doesn't soak up water the way Fiberglass does and that vermin tend not to like it either.

Fortunately, the fiberglass facing dries out, but absorbs little if any water, as it is essentially spun glass, and retains its' original shape. Don't know about mineral wool. However, this isn't the case with cellulose, which absorbs water, due to the fact that it began its' life as newsprint. It's an interesting sight to see a drywall ceiling that collapsed where the cellulose kept absorbing water during a roof leak to the point that it exceeded the limited strength of the drywall.

Although some rodents will nest in it, although they don't eat or, or apparently chew on it.

RM209

 

[LaneRover]

Although some rodents will nest in it, although they don't eat or, or apparently chew on it.

RM209

I did find two dead mice that had nested in the blown in cellulose that is above the ceiling in the room.

 

[DEnd]

Fortunately, the fiberglass facing dries out, but absorbs little if any water, as it is essentially spun glass, and retains its' original shape. Don't know about mineral wool. However, this isn't the case with cellulose, which absorbs water, due to the fact that it began its' life as newsprint. It's an interesting sight to see a drywall ceiling that collapsed where the cellulose kept absorbing water during a roof leak to the point that it exceeded the limited strength of the drywall.

Although some rodents will nest in it, although they don't eat or, or apparently chew on it.

RM209

Fiberglass and cellulose have about the same drying potential, as they are both very vapor open. When I was a child we had to redo our living room ceiling twice due to roof leaks, both times it the ceiling collapsed because the fiberglass got soaked. Using mineral wool, or fiberglass vs cellulose will not mitigate that failure.

 

[DekeT]

So my cousin was telling me recently that he heard that fiberglass insulation was junk. He said that recent research has found that the previous idea of how it would provide an R-value was wrong. He heard this from a professor at Kaplan. I guess the teach is on the state board that sets construction standards and practices. He says they've done numerous studies.

Has anyone else heard anything like this?

I just calling this whole thing B.S. You live in Minnesota, do you have a construction standards and practices commission? No!(http://mn.gov/portal/government/state/agencies-boards-commissions/index.jsp#A)

Does MN have a Kaplan U location? No. Your cousin punked you.

 

[zhaddock]

News flash, all universities are for profit.

Not even remotely true

 

[70chevellegsp]

I call fiberglass 'economical', as it's the least costly insulation available. When coupled with a proper house wrap with taped seams, window & door flashing, and proper installation of roofing and underlayment, it will do the job it's intended to do. Cellulose will do it much better, at a much higher cost. The benefits are better R value for the same volume, sound control, no air infiltration, and the biggie, more fire resistant. (google the tests and a you'll see the time difference between a test house being engulfed in flames between the two) Open and closed cell foams 'can' be better than fiberglass and cellulose. The issue (aside from cost) is that they seal so well that you may need to add an air exchanger to your HVAC system, which adds more cost.

That all being said, this is not NEW information. Cellulose and foams have been around for decades. The manufacturers of each will tell you the glowing benefits of each.

 

[bannerd]

I couldn't find anything on this. I would have to say that this isn't correct information either. I heat with wood and many times during the cold season the fire will go out early. The house retains the heat very well, if the insulation didn't work the -30F would be waking up the kids. Heat loss takes a few days before the house gets around 40F-50F

 

[Denwood]

One of the issues with fiberglass is convective heat loss within wall cavities and attics. Grab a piece of fiberglass and blow through it, particularly in the same axis as the fibers run.

There was also research on convective heat loss in blown in glass, which dramatically dropped R value at low temps, when convective loss would be greatest. The industry claims this issue has been resolved.

I used a combination of 2"spray foam (air seal) and R60 of cellulose in our attic retrofit. We also observed a dramatic sound reduction after doing blow in cellulose in the house which had zero insulation previous.

In the net zero housing research being done in Alaska, (YouTube - net zero , Alaska) 18" dense pack cellulose in wall system is being used to store and release moisture to keep inside humidity at healthy levels at -50. This research is being done with both temp and humidity sensors along with data logging. The YouTube series on these builds is the best I've seen so far.

 

[nadogail]

The credibility of the person making the statement "Fiberglass insulation is junk." has not been established to my satisfaction.
I think that the person making that statement is so full of it that their eyes are brown.

 

[BruceMc]

In the net zero housing research being done in Alaska, (YouTube - net zero , Alaska) 18" dense pack cellulose in wall system is being used to store and release moisture to keep inside humidity at healthy levels at -50. This research is being done with both temp and humidity sensors along with data logging. The YouTube series on these builds is the best I've seen so far.

Along those same lines, there's lot's of good information at our local CCHRC -

http://www.cchrc.org/

 

[cowboyjosh]

If fiberglass is junk, reckon I have allot of pissed off homeowners. I have more then a couple hundred custom, million dollar + homes, with fiberglass batts in the walls, and blown in fiberglass in the attic. Sometimes we go cellulose in the attic, but always batts in the walls.

Mr. Kaplan instructor is probably the same guy (a home inspector) who told my clients that Pella and Andersen windows are all "junk" and wouldn't install them or trust a builder who does.

 

[Denwood]

Fiberglass is not junk. It works. There are better products though in my opinion.

 

[walrus]

Fiberglass works best with a tight cavity, no air movement. If you have a sieve of a building, fiberglass doesn't do its job.

 

[ddawg16]

So, what company is that professor aligned with which produces a better product?

In my experience, 'professors' who have never had a 'real' job tend to live in a very narrow world void of real world experience and common sense.

 

[Radix2]

The best is the enemy of the good...