Blown in Cellulose or Fiberglass

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newbieinCT

Feeling the Heat
Sep 26, 2013
265
Danbury, CT
Quiz for the insulation peeps out there....can you help?

I'm attaching three photos. 2 from one attic, 1 from another attic in the home. We had insulation blown in.
Can you tell me if it is loose fill cellulose or fiberglass?

If you will indulge me, I'll explain more after I hear the responses. I dont' want to sway opinions with the backstory, yet. Basically, I'm having a debate with the contractors :)

So, cellulose or fiberglass (L77 ProPink)? Thanks! Meg
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It all looks like cellulose to me. I've installed it myself in my houses.
Went into the attic with a 2 day shadow and came out looking like Santa. That stuff really flies!
Maybe a way to tell absolutely (although I'm pretty sure from the photos):
-Although treated with something like borates I believe the cellulose will eventually burn.
-I believe fiberglass melts before burning.​
 
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Looks like cellulose to me as well.... Dad have loose fiberglass and it dosen't look like this, you can still see the "fiber" it is more in chunck than loose like blown in cellulose. I did put 24 in off blown in cellulose in my qttic and your pict looks like that.
 
Looks like newspaper to me also, blew a ton of it in previous place about 20 years ago. Yep came back down from attic looking like abominable snowman . Sure made a difference on that place. At the thime cellulose was less cost wise than the glass and I was on a tight budget.
 
My fiberglass is white like snow and doesn't itch. I see white blobs in your photos there so I am worried there is a mix. When I've worked with blown in cellulose it didn't have those white curds in it and you could actually look close and see the letters on the recycled newsprint. Can you see this detail?

Get it wet. fiberglass gets tight like a snowball but paper turns to well pulp applesauce. Once dry you can refluff the FG but the pulp turns into paper mache.
 
Really though, who cares? Turns out both are quite good at insulating. You need more thickness with one of them to get the required R value. You could have gone much thicker I would think.
 
Thanks, everyone!
I believe it is cellulose, as well :)

All the pictures of blown fiberglass shows it as very PINK, not gray.

Here's the backstory. We did A TON of reserach when deciding on what to get in our attics/walls/etc. We finally decided blown in cellulose in the attics was our best option considering our location, house, current insulation, etc. We brought in a few contractors and heard what they had to say - listened to all the sales pitches for fiberglass, cellulose, foam, etc. Finally decided on the company that best fit our needs, they recommended cellulose in the attics (we have 3 seperate attic spaces)

On the first day walk through, the project manager says he thinks fiberglass is better for attics. I didn't research fiberglass,. I tell him so, we talk a bit and I een said that if I could have time to research, I'll consider the fiberglass b/c he is the expert. There's a lot of different things going on int he house, air sealing, blown in cellulose in attics, crawlspaces, kneewalls, exterior walls, foam in basement - so it was a confusing day, but I am 200% sure that I did not agree to fiberglass. The house is pretty complicated, so I have been VERY aware of what is going on and staying ontop of it. Anyway, three weeks later, we get the final invoice and it says Fiberglass was installed in the attics. I figured it was a mistake, so I emailed the office manager. She confirmed the project manager said it was fiberglass. I'm still confused b/c I remember the discussion. I email the project manager and the sales guy, both were there during the conversation about cellulose vs fiberglass. They both write back saying that we decided on fiberglass.

I would be willing to believe them, if I hadn't been so on top of this and they hadn't made multiple errors in communication. I know we wanted cellulose in the attics. I even went up and checked to confirm it's cellulose and took photos. I haven't sent them to them yet becaues both my husband and I wanted to hear what others thought. I wasn't sure if there was gray-ish fiberglass. I wasn't able to find any unless it was "old".

Anyway, thanks for the information. I have much more confidence to call the company now and let them know they are fools. Well, I'll say it nicer than that. I'm pretty sure the photo evidence will show them without me saying a thing. It seems like they did put cellulose, like we had agreed, and then forgot and decided between the two of them that we chose fiberglass.

So frustrating!!!
Thanks again everyone :)
Meg
 
Really though, who cares? Turns out both are quite good at insulating. You need more thickness with one of them to get the required R value. You could have gone much thicker I would think.

You are right - it doesn't matter too much. We preferred cellulose b/c it's heavier (less air movement) than fiberglass and also less flammable. Also, I wanted to be sure we weren't going to have an issue with the rebates - so much of our issue is with the paperwork. Also, it has confirmed (to me) that this company doesn't know which end is up most of the time. We had communication issues throughout the project. I hate that they think I'm stupid and talked down to me for being a woman, when I actually had a better idea of what was going on than they did most days. I was correcting them. I'll have to let that slide and just remember never to use them again. For now, our house is warm. We have cellulose. I know I'm right, so as long as we get the rebates, I'll be happy!!
 
All the pictures of blown fiberglass shows it as very PINK, not gray.

You're wrong here. My last two houses had pure white fiberglass blown in insulation. Not grey at all, but certainly not pink. Pink is common with batts from the pink panther company (owens corning I believe)

You are right - it doesn't matter too much. We preferred cellulose b/c it's heavier (less air movement) than fiberglass and also less flammable.

Are you kidding? You think shredded newspaper is LESS flammable than melted sand? Cellulose has a lot of things going for it but being less flammable is not one of them.

I plan on blowing in cellulose for my next attic job mostly due to the superior air sealing qualities. Weight is a negative in any ceiling.
 
You're wrong here. My last two houses had pure white fiberglass blown in insulation. Not grey at all, but certainly not pink. Pink is common with batts from the pink panther company (owens corning I believe)


Are you kidding? You think shredded newspaper is LESS flammable than melted sand? Cellulose has a lot of things going for it but being less flammable is not one of them.

I plan on blowing in cellulose for my next attic job mostly due to the superior air sealing qualities. Weight is a negative in any ceiling.

I saw some lighter fiberglass online too, which is one of the reasons I chose to post here and see what others thought. The company uses L77 ProPink insulation - it is pink. I googled that brand, specifically, and the photos of it blown in are definitely pink. Also, they had a few bags in the truck and they were definitely pink.

While I haven't done too much comparison on the fiberglass vs cellulose flammability (there are a ton of websites steering you in either direction, although I found more pointed to cellulose as superior in attics), I guess I should have been clearer. I was trying to keep things simpler - I meant less flammable than spray foam (one of our other options).
 
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Most definitely cellulose. Attics are so easy anyone can do it themselves. Wall cavities are another matter . Not likely to make any mistakes in the attic. WHen you just pay for the cellulose and about $20 to rent the machine it is really a low cost job.
 
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You're wrong here. My last two houses had pure white fiberglass blown in insulation. Not grey at all, but certainly not pink. Pink is common with batts from the pink panther company (owens corning I believe)
I have blown in fiberglass insulation at my house that is pink. And can buy more bags of it at HD which can be blown in using their machines.

Are you kidding? You think shredded newspaper is LESS flammable than melted sand? Cellulose has a lot of things going for it but being less flammable is not one of them.
Interesting related video.
Consider the source though.
 
I have blown in fiberglass insulation at my house that is pink. And can buy more bags of it at HD which can be blown in using their machines.


Interesting related video.
Consider the source though.


To be clear, FG blown in insulation can be pink, white, brown, etc. not just pink.

Depending on who makes the video you can always make the other guy look bad. It's not the initial fire that makes cellulose so scary, it's the rekindle after you think you've put the main fire out since the cellulose can "hold a coal" for so long. I've seen so much propoganda on either side of this that I've decided both are good but the air sealing superiority of cellulose gives it the nod.
 
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You are right - it doesn't matter too much. We preferred cellulose b/c it's heavier (less air movement) than fiberglass and also less flammable. Also, I wanted to be sure we weren't going to have an issue with the rebates - so much of our issue is with the paperwork. Also, it has confirmed (to me) that this company doesn't know which end is up most of the time. We had communication issues throughout the project. I hate that they think I'm stupid and talked down to me for being a woman, when I actually had a better idea of what was going on than they did most days. I was correcting them. I'll have to let that slide and just remember never to use them again. For now, our house is warm. We have cellulose. I know I'm right, so as long as we get the rebates, I'll be happy!!

Was there a price difference?
 
If you have soffit venting I would be more concerned that they might have blown it where it blocks the vents than I would be with the material. For the record, the blown in fiberglass insulation in our attic is snow white. The pink stuff just means it came from Owens-Corning. Trademarked by them.
 
If you have soffit venting I would be more concerned that they might have blown it where it blocks the vents than I would be with the material..
Good point: I had to go back and re-do a rental property where the attic floor joists were open right out to the face plate behind the gutter ,allowing the 12" overhang to be filled with insulation. It caused tremendous ice damming and water leaks all winter. I had to clear the cellulose out of that area and install a blocking board on top of the wall plate to ensure insulation went only to the wall edge an no further. It cured the problem completely. Air flow must be maintained from soffit vent and between roof joists up to the roof ridge with a ridge vent if possible.
 
You're wrong here. My last two houses had pure white fiberglass blown in insulation. Not grey at all, but certainly not pink. Pink is common with batts from the pink panther company (owens corning I believe)

The previous owner of this joint had fiberglass blown into one wall. Its yellow. So there is at least 3 colors. Ive also seen bats in pink yellow and white.


[ Of course the PO didn't bother with all the other walls and the attic :confused: which we of course had done in cellulose, grey just like yours. ]
 
That is most definitely cellulose. I hate fiberglass. Its one thing in batts hidden in the walls. But I can't stand it exposed anywhere because it is such an irritant. I'm so glad my attic has cellulose because when I occasionally have to go up there I come down covered soft cellulose instead of itchy fiberglass.

OP, that is an odd story, but at least it looks like you got what you were looking for.
 
That is most definitely cellulose. I hate fiberglass. Its one thing in batts hidden in the walls. But I can't stand it exposed anywhere because it is such an irritant. I'm so glad my attic has cellulose because when I occasionally have to go up there I come down covered soft cellulose instead of itchy fiberglass.

OP, that is an odd story, but at least it looks like you got what you were looking for.

Get with the times man, the blown fibreglass doesn't itch anymore. It's like shreddd cotton balls now. Actually a relatively pleasant experience. I just put 6 can lights in from the attic and had to swim in the stuff. No itch. Even modern batts are much better.
 
Just because they removed some of the additives that cause the worst of the itch doesnt mean its totally safe to be exposed to. I still wouldn't want to get the fibers in my lungs.
 
My problem with fibreglass has nothing to do with the itching. Iv found it does not seal up the cavity near as well as cellulose and it shrinks over time. They may fix the shrinking with new products but they really cant fix the fact that you can never quite get the cavity well sealed unless you are blowing it in with a machine rather than rolling in batts.
 
Get with the times man, the blown fibreglass doesn't itch anymore. It's like shreddd cotton balls now. Actually a relatively pleasant experience. I just put 6 can lights in from the attic and had to swim in the stuff. No itch. Even modern batts are much better.

Well I suppose that I shouldn't comment on blown fiberglass as I've never dealt with it. But I have certainly dealt with modern fiberglass and "better" it might be but I still find it to be terrible to deal to handle and certainly not something I want to breath. Maybe I have sensitive skin (and lungs) ;) ?

I would take blown cellulose over fiberglass in an attic any day.
 
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Before dissing cellulose insulation, ground up newspaper, as being a fire issue, be sure to google up those videos that show a guy putting a penny on top of a pile of treated cellulose on his bare hand, then using a blowtorch to melt the penny. The molten copper rolls off the wad of cellulose, leaving the cellulose barely charred on its surface. Imagine TRYING to get a fire going in that stuff, deliberately, and failing.
 
Before dissing cellulose insulation, ground up newspaper, as being a fire issue, be sure to google up those videos that show a guy putting a penny on top of a pile of treated cellulose on his bare hand, then using a blowtorch to melt the penny. The molten copper rolls off the wad of cellulose, leaving the cellulose barely charred on its surface. Imagine TRYING to get a fire going in that stuff, deliberately, and failing.

Counterpoint.

 
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