Cellulose vs. Fiberglass Insulation

[enigma]

I was quoted cellulose insulation by LENNOX dealer and I was quoted fiberglass insulation by insulation specialists. The LENNOX salesman told me that their quote was twice more expensive than the fiberglass insulation because cellulose is more expensive. Is that true?

Also a construction contractor told me to avoid cellulose, or as he told me shredded-newspaper product (???). While others say that cellulose is a better insulation than a fiberglass. Any comments?

[uktra]

Why would an HVAC contractor quote insulation? What kind of application of cellulose was he talking about? loose spray in attic? wet spray in walls? Net and dense pack in walls?

[dec]

hummmmmmm are we saying that Lennox is spreading they wings in other directions. Boy that service tech is going to be a little upset when things are slow and he becomes an insulator but Im sure that insulator is going to probably be asking techs wage being he will probably be better at insullating. lol Are you really saying that lennox is figuring insulating their duct by just putting cellulos insulation around it than wrapping it with any insulation?

[enigma]

LENNOX salesman (remember? the guy who took photos of my old ductwork in the crawlspace and basement) was talking about wet spray in attic and lose spray in crawl space (or is it vice versa?). Anyway I was quoted 3k for attic insulation (just attic) of a 1600 sq. ft. home which already has some fiberglass insulation in the attic.

Yes, that company does insulation or maybe they subcontract it? Quotes by insulators were way lower. But I'm not sure cellulose or fiberglass was quoted by non-hvac insulators.

I am talking NOT about DUCTWORK INSULATION, but about ATTIC, BASEMENT ceiling and CRAWLSPACE INSULATION. HVAC LENNOX does ATTIC insulation. Of course they do ductwork insulation too, but I'm not sure WHAT MATERIALS are used (and what are best) for ductwork insulation (?).

Is CELLULOSE better or FIBERGLASS for a house insulation?

[dec]

Just my opinion I like fiberglass, as far as the R value they will put in how ever many inches of cellulos or fiberglass to get to the r value you need. That way as far as one being any differant as far as the insulation value that you get is a moot point.

[uktra]

The HVAC contractor probably subs it out and is charging too much. I like cellulose better than fiberglas, because it does not lose R value when the temperature decreases. Air does not go through it as well as it does fiberglass (which decreases R value). Search out an insulation contractor that does cellulose--you will find the price a lot lower.

[pstu]

You might think about this: Cellulose based insulation is going to be permeated with borax or some kind of insect poison. Cellulose is going to disintegrate into dust after enough years, and some of that dust is sure to get into the house. For this reason a Houston local builder who has a radio show (Tom Tynan) insists he will never put cellulose insulation into a house he builds. He thinks in a few years there will be a whole remediation industry devoted to sucking that material out of houses. Is he right? I cannot say. Just something to think about.

-- P.Student

[dallasbill]

Up until about a year and a half ago, Tom Tynan was slamming ICF homes too. Hmmmmmm.....

[pstu]

I have heard Tynan say lots of things that I think are flat out wrong, by no means am I saying he deserves guru status. But I think it's worth following his logic about cellulose. We know it disintegrates over time, do we not? We know attic dust will get into the home, at least some of it, right?

In the 1980's my home had cellulose insulation put in, that was a really dusty home though I can only speculate why.

I had not heard Tynan diss ICF homes too hard, that would have been interesting. I don't think that guy understands ventilation and humidity control at all. However he has been fortunate to link up with Central City Air which does think long and hard about those things.

When Tynan says something I try to match it up with what I do know and see if there is much discord. In this case I think it would be playing it safe to avoid exposing one's family and pets to the chemicals used in cellulose. Nobody seems to have enough info to make a clear and strong statement as far as I know, so we are left to our own opinions.

Best wishes -- P.Student

[uktra]

I am confused--what would cause cellulose turn to dust?

[enigma]

So which one do you think (or know) should be less expensive per sq-ft: cellulose or fiberglass insulation?

[mjballweg]

Great issue. I am trying to make the same decision on a new house. The insulation contractor will do either damp spray cellulose, R-13 fiberglass batts, or R-15 fiberglass batts in 2 by 4 exterior walls. The contractor told me the price between R-15 and cellulose would be about the same with the cellulose coming in at about R-13; roughly 10-20% higher than the R-13 batts. However, he said that in his opinion the cellulose is a much tighter air seal. I asked about the possibility of the cellulose settling in the walls and the insulation contractor said it will not happen; the amount of cellulose sprayed takes that into consideration.

An hvac contractor and another professional member on this board have both told me that they would recommend cellulose over fiberglass batts, provided it is allowed to dry properly. Also, Dr. Joe Lstiburek lists cellulose as an alternative to fiberglass batts in his materials.

Has anyone ever tried to do an A to B comparison between the two? Uktra or anyone else, have you had experience with cellulose? Has anyone had a bad experience?

[-80guru]

What is an ICF home?

[mark beiser]

Cellulose has a higher R value per inch, but it breaks down more over time than fiberglass.

When cellulose breaks down, it gets very dusty, and becomes a food source for lots of things. It is nasty to work around when doing repairs in a home that is insulated with it, so I charge more for the repairs when there is cellulose insulation.

I won't ever use it in my own home, or buy a house that has it.

[uktra]

No scientific evidence that I have seen shows that cellulose treated with the boron derived chemicals "breaks down" nor becomes "food ". In fact the boron chemicals make cellulose undesirable for insects, rodents, ect. The only problem I have with wet spray wall cellulose is the wet part. Cavities are not allowed to dry long enought before drywall is placed. I recommend net and dense pack cellulose to air seal wall cavities because it is put in dry. The key thing is, that it gets into all the crooks and crannies to prevent thermal voids. Yes it is nasty dusty stuff--but it works!

[binford]

Cellulose is shredded-newspaper treated with borax.
I install fiberglass batts in my attic; this way if needed I can move them, to install a light or fan, etc.
For a crawl space, I would look to ridged insulation with foil on both sides. No paper for mold to grow on.

[mark beiser]

Yes, lets put nasty dusty stuff, treated with boron, all over the place in the house!

No sale, you can keep the cellulose insulation. Maybe some of the new products will hold up better, but the cellulose insulations they have been using for the last 25+ years are crap.

Oh, and it doesn't matter what they treat it with. Cook cellulose insulation in a Texas attic for a few years and not only will it become a food source for insects, it can loose most of its flame retardant properties too.

[Edited by mark beiser on 01-30-2005 at 12:06 AM]

[dallasbill]

It's been really interesting reading this thread, which is about the same topic that has been debated for ages. I am not going to attempt to defend either side.

All our insulations is foam. We chose cellulose for the wall separating our garage from the conditioned space. It has lots of stuff threading through it. Having ICF walls around the home, we did not want to compromise this (unconditioned) wall with fibreglass. We don't want any wall voids, and we will not get that w/ cellulose!

Everthing I have read points to no breakdown of modern cellulose product.

As for people who complain it's treated with boran or borax:
Boron/borax is used in all sorts of external, organic-approved programs for mold/carpenter ant/termite protection. Cellulose is external to your living space. Read that again before you post horrors again about boran/borax. Are you saying don't buy a house treated w/ Boracare on all studs, too? When it's the number 1 accepted organic control for wood? Hmmmmmmmmm....??


Used correctly the walls w/ cellulose are sealed... just like I would assume fibreglass would be.

And, sealed correctly neither one has been studiously shown to be a health concern.

Plus, why do people here keep talking about stuff from "the past 25 yrs" instead of stuff used now?!

YMMV... ;-)

[Edited by dallasbill on 01-30-2005 at 02:21 PM]

[cem-bsee]

I first put cellulouse into my house in 1967 --- still there -- Marion IN -- Boric acid is fire resistant & works against most insects, including cockroaches! -- it does pack tight -- yes, it is ground up newsprint -- BTW, it seems to me that this process was started near Marion.

I have some old newspapers which are over 100 yr old, including 1898 wedding announcement -- has not crumbled into dust yet! just gotten yellow -- and I can state that it was in a box which was in extremes of environment. I have seen several houses having newspaper as wall paper -- still good after 40+y.

I put cellouse into my present house.

Now days good installers can pack the walls with cellulose. Said packing will stop "bridging" = heat transmission thru the gaps at the sides of fiberglass bats.

the best technique is to use hollow studs made of 2x4, but of 8" width, pack with cellulose, then sheet with plywood covered with Styrofoam. Styrofoam & the hollow studs breaks the heat transfer thru the wood. Wood is not a good insulator. Styrofoam only for sheeting is POOR. In areas with mild temperatures, turn the 2x4 sideways to have 6" walls -- in both cases on 24" centers.

[tuccillo]

Originally posted by cem-bsee
I first put cellulouse into my house in 1967 --- still there -- Marion IN -- Boric acid is fire resistant & works against most insects, including cockroaches! -- it does pack tight -- yes, it is ground up newsprint -- BTW, it seems to me that this process was started near Marion.

I have some old newspapers which are over 100 yr old, including 1898 wedding announcement -- has not crumbled into dust yet! just gotten yellow -- and I can state that it was in a box which was in extremes of environment. I have seen several houses having newspaper as wall paper -- still good after 40+y.

I put cellouse into my present house.

Now days good installers can pack the walls with cellulose. Said packing will stop "bridging" = heat transmission thru the gaps at the sides of fiberglass bats.

the best technique is to use hollow studs made of 2x4, but of 8" width, pack with cellulose, then sheet with plywood covered with Styrofoam. Styrofoam & the hollow studs breaks the heat transfer thru the wood. Wood is not a good insulator. Styrofoam only for sheeting is POOR. In areas with mild temperatures, turn the 2x4 sideways to have 6" walls -- in both cases on 24" centers.

Have you looked at closed-cell spray foam insulation?

[mam123]

I recently had closed cell foam sprayed in my attic filling the 2x6 open and floored spaces over the rock wool originally installed in 1950. It not only insulated the attic, but it sealed many air leaks. 5.5 inches give me R-30, and the unexpected benefit is that my large self can now "swim" on top of it to the edges of the eves without the fear of an errant foot breaking through the sheetrock with very little pressure. It was installed for a lot less than your 3K bid in my 1580sf.

[dallasbill]

All good points.. thanks!

-80guru... ICF is insulating concrete forms. A way to build walls w/ poured concrete inside EPS blocks or panels. See http://www.forms.org/

[enigma]

"Cellulose is shredded-newspaper treated with borax". OK, then we all know that newspaper contains lead paint, which makes cellulose or shredded newspaper insulation unhealthy and undesirable. Why not insulate with wool? In addition - what is borax? Is it harmful to humans?

[bluetooth751]

Originally posted by perpetual_student
You might think about this: Cellulose based insulation is going to be permeated with borax or some kind of insect poison. Cellulose is going to disintegrate into dust after enough years, and some of that dust is sure to get into the house. For this reason a Houston local builder who has a radio show (Tom Tynan) insists he will never put cellulose insulation into a house he builds. He thinks in a few years there will be a whole remediation industry devoted to sucking that material out of houses. Is he right? I cannot say. Just something to think about.

-- P.Student

I 2nd that movement

[uktra]

Anyone can say anything. Until it is based on scientific evidence, saying something does'nt mean much. I have done a lot of reasearch on fiberglass and cellulose. The story from the cellulose industry was that fiberglass was carcinoginic. The evidence now is that it is not. I recommend net and dense pack cellulose in new homes because it does a better job of insulation for the money. Mr. Tynan can say what ever he wants--but what is he basing it on? As far as being toxic, there has never been any research that I know of that suggests boron products in cellulose are toxic to humans.

[pstu]

DallasBill, I would like to ask you what is a "syncophant". Am trying to figure out whether you called me a bad name. I'm just trying to figure out the truth here, if it is contrary to what you think is so, there might be better ways to reach harmony than calling names. I will try not to do so myself.

It seems lots of sources consider cellulose benign. For an article on how cellulose is supposed to be, you can read this:
http://www.diynet.com/diy/he_home_insulation/article/0,2037,DIY_13895_2274825,00.html

Also when I search for problems with fiberglass, I find stuff written about that also. Mostly it's problems with itching and getting too much in the lungs and related stuff. Being basically a form of glass, fiberglass seems relatively inert. To me itching seems more understandable and less risky than a soup of printer inks and mold-killing, insect-killing chemicals.

Based on what I know, it seems questionable that cellulose will *not* decompose into dust over time. I cannot explain the process other than it's an organic product (with lots of surface area) dosed with some poisonous chemicals to keep mold, insects and whatnot from eating it. Using recycled newsprint as it does, you have to evaluate the safety of inks from that source. I'm not at all against using chemicals when they serve a purpose and are studied to be safe, however what is "safe" is a judgement that changes over the years. I remember when tri-chlorobenzene was considered safe and chemical plant employees took it home in gallon jugs for cleaning greasy car parts. The solvent for Liquid Paper (was based in your area) was that chemical, sold in thousands of stores to anybody who had a dollar or two -- now it's considered a hazardous material.

Asbestos is another material once considered benign, which now is shunned around humans. Like the cellulose in your walls, very possibly it will just stay there and not cause any problems. Very possibly leaving it in place is safer than trying to remove it. For both asbestos *and* blown cellulose.

Some people seem to have acute problems when exposed to *something* in cellulose insulation, very similar to what I know about the mold-in-walls problem. I really want you to read this article on case studies:
http://www.hhinst.com/Artcellulose.html

Again I'm not saying this it the last word on the subject, but it seems to me a prudent person would want to learn more before possibly exposing his family and pets to the material. But I am enjoying reading the opinions of others and haven't stopped thinking and learning more about it.

Hope this helps -- P.Student

[Edited by perpetual_student on 01-30-2005 at 01:23 PM]

[mark beiser]

In case anyone is wondering why I seem to have an "unreasonable" hate for cellulose insulation, it is because I frequently get sick right after any install in an attic that has cellulose insulation.
Even after I started using a respirator with real filters instead of just a dust mask.

[uktra]

There is a difference in being toxic and having an allergic reaction to a substance. I am sorry Mark has an allergic reaction to cellulose and I am sure he hates working in attics that have it installed. That being said should one base an important decision to put fiberglass or cellulose in their own home based on this information? I don't think so. In new construction, one needs to air seal the home. To do the sidewalls you can do this with fiberglass, if you airseal the drywall and all penetrations. One then must install the fiberglass perfectly to avoid all voids. These things can be done, but it is rare in the homebuilding business. On the other hand, netting and dense packing cellulose provides an airtight and voidless stud bay by the nature of its application.

[dallasbill]

P-Student... my bad... it was the wrong word to use.
Sorry... I have changed my post.

AND, before you make eroneous statements that boron and borax are toxic chenicals that kill insects and mold, I suggest that you use the Internet to study it. It does not kill them.

It does not allow mold to start in the first place. It removes wood -- renders unusable to their systems -- as a food source for termites and as a tunneling & nesting source for carpenter ants.

See here for Bora-care wood treatment: http://www.nisuscorp.com/boracare.html ...I would not build a house nowadays WITHOUT it.

The same process works in the cellulose. Please research before making erroneous statements that it is a toxic insect/mold killer.

And PS... if you are old enough to remember the commercials of the 60's for 20-Mule Team Borax detergent, it contained broax as a whitening agent for clothes. You can still get such in products today.

[Edited by dallasbill on 01-30-2005 at 02:34 PM]

[pstu]

Let me clarify, it was never me who named specific chemicals before. I have a BA degree in Chemistry and would not name ingredients unless I knew, and I don't. I don't want to get into any kind of a flame war but am not against discussing a contested subject with facts. I understand Lstiburek is all in favor of cellulose insulation and that counts for a lot, but the logic of Tynan's argument *still* seems reasonable to me. Let me quote some things which I have found on the net, and I am inviting correction if any turn out to be untrue:

http://www.builtgreen.org/articles/0209_cellulose.htm
"...Most cellulose insulation consists of ground, recycled paper (primarily old newspapers) plus a chemical added for fire retardancy. The ratio is roughly 85 percent paper to 15 percent chemical additive..."

The above source is highly in favor of cellulose. My observation is -- with chemicals being 15% of the total product, I would want a full inventory of what all of those chemicals are.

http://www.centralfiber.com/xcell.html
"...The same non-toxic, 100% borate chemical that gives Xcell its fire retardant qualities, also acts as a fungicide helping control mold and mildew..."

The above source is a seller of cellulose. My question is, can something be non-toxic and a fungicide at the same time?

http://www.wconline.com/CDA/ArticleInformation/features/BNP__Features__Item/0,3299,108152,00.html
"...Borates and boric acid, chemical additives to cellulose insulation, are known toxins which can be fatal to humans..."

The above is supposed to be neutral teaching. It seems to me contradictory to other statements above.

http://www.buildingscience.com/topten/south.htm
"...Dilution is not the solution to indoor pollution in the south. A bunch of cowardly Yankees refused to target the real issue of source control in many buildings due to the related issue of material off-gassing. Too many manufacturers of building products would get pissed off. What? You want me to actually tell you what I put in my product? And then tell me I can't put it in? No way!..."

The above source is Lstiburek himself, only on another subject -- building with materials containing unknown chemicals. Do you see the irony? With cellulose insulation we are talking about a mix of 15% chemicals, some are un-analyzed (recycled newsprint), and the vendor pretends everything is perfectly OK.

The definition of "poison" or "toxic" deserves some reflection. Many substances are toxic in certain doses, and not at lower doses. The missing link that bugs me is, just what is left of the inks from recycled newsprint? Those people who report health problems, are they somehow WRONG??? Are the other chemicals really safe enough to put in contact with your family? Or must they be sealed forever to be safe? And do we know everything about this already, or will something bad be discovered in the future?

I entertain doubts. I cannot say much more with certainty.

Hope this helps -- P.Student

P.S. I do understand the allegation about fiberglass being a suspected carcinogen. Does that pass the reasonbleness test? Only if due to tiny glass pieces disturbing your cells, the way asbestos was found to do. It is my opinion that we would *know* by this time, if fiberglass behaved like asbestos. So I think it is probably not a carcinogen, and probably no more significant to health than other forms of glass, in a chemical sense. Whereas dyes and certain other chemicals may be IMO more likely to produce health problems, whether cancer or something less scary.

[Edited by perpetual_student on 01-30-2005 at 04:44 PM]

[uktra]

Perpetual student--I don't understand the statement "but the logic of Tyman's argument still seems reasonable to me". What logic? What facts? I think if you do more reasearch you will find that most scientists will say that both fiberglass and cellulose are safe for insulation product use. As far as Joe Lstiburek, the quote from him was on the materials of the house that offgas terribly like paint, carpet, and other large surface products that are exposed in the house, not the low offgassing products behind the walls.

[mark beiser]

I don't just have an allergic reaction to the crap. I get real sinus and ear infections when I have to grub around in the junk when its 20+ years old.

Put it in your walls all you want, but do everyone a favor that ever has to work in your attic in the future, DON'T HAVE IT BLOWN IN THE ATTIC!!!

And yes, the possibility of severe allergic reactions MOST DEFINATLY should be a considderation when choosing any building material!

Open or closed cell foam is a much better product anyway, and it won't settle, ever.

[pstu]

Sorry that I have so far been unable to explain my position to everyone's satisfaction. I will give it one more try and then give it a rest.

Tynan's logic as I see it is this: he will not trust a new building method or material until it has been out in the market a very long time. I would estimate 10-20 years. That means only wanting to use methods and materials which have stood the test of time.

Because I am a homeowner and not HVAC pro, and because the subject is chemistry, I choose to follow that very cautious attitude rather than obey what OSHA or our government testers say. There have been too many cases where a chemical was well accepted in its day, and *later* they learn it is terribly toxic or carcinogenic. Examples I am thinking of are:
1) An ingredient in ladies' makeup, toluene diamine, was found to be a known carcinogen in lab animals.
2) A dye widely used in margarine in pre-war Germany, was found to be a carcinogen.
3) Tri-chlorobenzene went from being considered highly safe in the 1970's, to being a suspected carcinogen and/or chronic toxin (I forget which) today.
4) Look how long it took us to figure out cancer was caused in huge numbers by cigarettes.
5) This isn't chemistry but building science -- Look how a whole wave of EIFS ("synthetic stucco") was put on homes, and now their liabilities are recognized.

If I was an HVAC pro I would grit my teeth and keep my mouth shut unless asked. I would talk up the true fact that there will be fewer voids with cellulose when properly installed. I would also remind everybody that a leak in an attic return duct may suck up dust from the attic and mechanically distribute it all over the house -- probably do a hard sell on duct sealing for that reason.

But as a homeowner, I will prefer not to trust a chemical solution until it is very conservatively proven to be safe for a decade or two. And we are not clearly there yet.

Best wishes all -- P.Student

[dallasbill]

P_Student... you are throwing up one straw dog after another. Every one of your points 1-5 has nothing to do with cellulose insulation and boron.

The wind blew southerly yesterday and I got in a car accident -- therefore I shall never again drive when the winds are from the south. Causal correlations where nothing exists!

You purport to "agree" with Tynan's "logic" when you know not why he says it -- you only agree because he has been a GC for 10-20 years. So, by that same causal logic, if he told you that you only needed a seer 8 A/C in Houston, and radiant barriers are a waste of money, you buy it. Except nowadays he advocates seer 12-13, strongly recommends radiant barriers in the attic, and as I said before: no longer slams ICF.

A leak in any attic duct will suck up dust -- it's there in spades in any attic, esp. an unsealed one! It has nothing to do with cellulose.

And, as a homeowner, you should look at borate products -- because if you read my previous link, which also contained MSDS links for it, you would have seen that it has been in use for well over a decade. And, near as we can tell from your last post, it's 10+ years of history before you will believe in something.

Therfore, in keeping with such logic, we now give permission to buy your first VCR... ;-)
And... did you know that newspaper ink has been vegetable dye based for at least 5 years now!?

[Edited by dallasbill on 01-30-2005 at 09:59 PM]

[enigma]

I've got a booklet from Applegate Insulation associate and on the front cover it says:

"The insulation you decide to purchase will affect you and your family for as long as you live in your home!"

Boy, they are NOT lying! It's the same as if I said:

"The air in your house will help you live as long as you breathe it in".

By the way, - they install cellulose insulation, the ones that quoted double price and explained that cellulose insulation is way much more expensive than fiberglass insulation - is it?

The booklet says cellulose insulation is environmentally friendly. But it says nothing whether it is human-healthy.

Why not use dried cow manure for insulation? That sure would not hurt you and your family.

[pstu]

Is DallasBill saying chemistry has nothing to do with cellulose insulation?

Saying that boron is the only ELEMENT (an element is not a chemical) to be studied for toxicity?

My opinion has much more to do with my background studying chemistry, and knowledge of just how long it takes to thoroughly study something. It really has little to do with Tom Tynan, he said something and I second that opinion because we both agree it's safer to be very conservative.

I am NOT saying you will have trouble with your own cellulose insulation in your wall. I am saying it's better your house and not mine, and emphatically there are houses where the exposure is going to be far higher than yours.

But I have to wonder whether you think the case studies I cited are false.

Regards -- P.Student

[uktra]

Pstudent--again I am confused. What case studies about chemical products in cellulose used for insulation? Boron products have been known for years. We know that if ingested in sufficient amounts it can be toxic. We are not eating cellulose. Cellulose has been used for 20 years or more. Other than very isolated allergic reactions, where is the burden of evidence? No offence to Mr Tynan, but if builders had their way, we would be building houses the same as in the 1800's. I can understand being careful about chemicals in the environment, but before we make statements about products, we need some hard evidence before we condem.

[pstu]

I would like to know if you would dismiss every case cited by Mr. Bowers, as a fluke. I gave the link earlier. I have given you the basic principles of my thought and several links to raise concerns, I probably cannot do a whole lot more to clear up the uncertainty in your mind. We may have to agree to disagree.

Cellulose insulation is 15% chemicals. The information as to exactly what is in those chemicals, has not been shown to me -- maybe you or somebody else can show me a link. Although it is not a pro's level of caution, I will not rest easy until there have been *good* studies as to the complete inventory of chemicals in that 15%.

Remember that at no time have I said cellulose insulation exposure *would* necessarily cause problems. But it appears to me pretty sure that it has, in certain cases in the past.

As a professional worker in the field, you pretty much necessarily accept higher exposure. I would too, and did while working in the chemical industry (but would study toxins more thoroughly and discuss it with educated peers as well). You get paid for that, and have little other choice. Forgive me for being more cautious with my own self and my family.

Best wishes -- P.Student

[uktra]

I have John Bower's book. One of my jobs is to help people build healthy homes. In John's book "the Healthy House" he also mentions problems with fiberglass insulation. What chemical compound is the pink dye to color the insulation. Are the binders formaldehyde? If not what are they? He states "it's very important to keep fiberglass insulation well separated from the living space. One report found that nearly all of 13 workers in an office reported various symptoms related to glass fibers entering the air due to improper construction methods". Are we to reject fiberglass as well? John states in his book "Nearly every type of insulation has been implicated in some health problem. Yet, with care in installation and material selection, a healthy house can contain insulation". One of my other jobs is recommending the best insulation for the money for energy effeciency. Untill there is some scientific bases that cellulose causes problems in properly built homes, I will continue to recommend this insulation for certain types of construction.

[Edited by uktra on 01-31-2005 at 03:19 PM]

[dallasbill]

This will be my last contribution here:

P_STUDENT... and anybody else who wants to take Tynan with a big grain of salt...

Do you know what upwards of 75% of daytime WEEKEND AM talk radio is in most urban markets, inc. the stations he is on in TX? It is bought time. Know what that means? It means someone (i.e. Tynan Construction Company, Or Ed's Gardening, or Ed Wallace's Automotive World, Or Sam's Financial Advice, or...) pays the stations for mass blocks of cheap time to air their shows. The radio stations get money and have to do nothing on weekends -- a lot cheaper and great margin! On TV it is called an infomercial and must be preceded by "this show was paid for by xxxx.

Tynan, et al, in turn get sponsors to pay them to give them commercial time and to give them "innocent sounding" plugs throughout the show to callers and listeners. At the same time, they are "selling" their services as experts, giving advice and you and everyone else believes it -- or considers the shilled source. And guess what they don't talk about or say they really do not care for? Companies or products that they do not use and do not sell airtime to on their show.

Like cellulose insulation companies....

[mikmic2]

After much research on this subject a few years back, I started using blown cellulose, with a high quality mask of course.

I reached this conclusion based on the fact it appeared all things were equal in the health department, as cellulose has came a long way since its first introduction. Fiberglass insulation is so porous that the convection that takes place in a properly ventilated attic will suck the heat out of the fiberglass insulation in to your attic and out the vents.

If you are going to blow fiberglass insulation in your attic, make sure you use at least 5" additional inches to compensate for the thermal convection. One other alternative that I ran across from a manufacturer was to blow a couple of inches of cellulose over the top of your fiberglass as a coating to stop the convection action from robbing the heat out of the fiberglass. But I figured if I was going to have to do that, I might as well blow cellulose in the first place.

Cellulose being much denser then fiberglass is much more resistant to the convection that takes place in your attic.

Don't believe me? Try this little experiment.

Take a household fan, and two window screens and put five inches of fiberglass without smashing it between the two screens, and face the fan so that it blows through the fiberglass, and run a smoke test on the other side. Then take 2 inches of cellulose clamped loosely in the screens with the same fan, and run another smoke test on the other side. You will see which is more porous and which robs the most heat out of your attic through thermal convection.

In the HVAC business we all know that heat moves from warm to cold, why make it easier for the heat do do that in our attics when it costs us money?

Once I heard this line of reasoning, which seemed to make perfect sense, I opted to go with cellulose.

As a bounus, cellulose manufacturers claim a higher r-value. As the temperature difference increases the effective r-value of fiberglass diminishes because of the reasons stated above. If that isn't enough, cellulose is also supposed to be more fire retardant then fiberglass. (Which came as a shock to me.)

Just my two cents.

By the way, I would rather snuggle up to cellulose rather then fiberglass, any old day. :-)

[binford]

Boric acid is used as eye wash and to clean your contacts. Crawling around in any attic insulation is not fun, that why they are suppose to have runways. I bought a full face mask, have yet to use on one of those sh!& jobs.
I still like batts because I can move them and put them back when done.

[-80guru]

When you drop a tool in cellulose it makes an outline of the tool which in turn makes it easy to find.

[energy_rater_La]

I have read John Bowers book also.
He has many valid points and there is a lot
to be learned from his book. Building Science Corp.
is also good source of unbiased information.
I do house diagnostics.
One of the main concepts is to keep attic & ambient
air out of conditioned spaces. Not only from
a IAQ viewpoint but also with energy efficiency
in mind.
Making sure that the air barrier between attic, ambient
areas and conditioned space is manditory.
If the attic and walls are well sealed, Air Tight Dry Wall Approach is installed, ducts and a/c boxes sealed, then the insulation material on the other side of that air barrier becomes much less of a health hazard.

Interesting thread.

[binford]

A bit off the subject, but as homes are being offered with higher and higher energy saving as a selling point. Soon all duct work will have to be run in conditioned space to obtain even more gain on energy savings.

[colerbuildingtech]

As an insulator, I would not recommend fiberglass, even though it has been the insulation of choice by many builders. Think about it - the same fiberglass is used in your furnace filter and does not stop air infiltration. The main consideration to look into is air infiltration. Cellulose is better when dense packed, but still allows air penetration. The spray foams are the best since they are excellent insulators and provide an air barrier that won't condense. You can check out the soy based spray foam at http://www.coler.com or http://www.biobased.net. It truly is a better solution than fiberglass and cellulose. If the foam was not around, I would use cellulose since it is a better air barrier, but still not the best and can have issues with fire situations and dust.

[pstu]

>>fiberglass is used in your furnace filter and does not stop air infiltration. The main consideration to look into is air infiltration.

Is it the job of insulation to stop air infiltration? Why should the vapor barrier be where the insulation is? I submit it is far better to have the vapor barrier on the cold side of the wall to avoid condensation problems.

The "thermos bottle" philosophy of sealing and insulating houses is not accepted by all building science experts. I'm suggesting if you propose an extremely sealed house, you NEED to be talking at the same time about designing a mechanical ventilation system for air quality reasons. This is its own engineering project, not just a window to open.

One of my former teachers used to say "you're building your own coffin" to anyone who proposed building an ICF, SIP or other highly sealed house. But he didn't speak one word about ventilation systems except to say "a house has got to breathe" (which would have been fine if he would only explain precisely what it means to "breathe"). His approach to return air paths was to recommend a one-inch undercut on all doors; I think there are far better solutions to that problem. Despite what I see as his shortcomings in teaching, he *did* motivate me to learn a whole lot more beyond his 1st class.

Best wishes -- P.Student

[Edited by perpetual_student on 03-16-2005 at 09:21 AM]

[paul42]

Quoting a couple of things from my "Energy & Environmental Building Associaton Builder's Guide for Mixed-Humid Climates"

"loose fibers and particulates of many sizes and many materials (fiberglass, rock or slag wool, cellulose) have been known to irritate many people. As long as proper precautions are taken during installation and proper containment and air sealing of these insulations is made, the health risk is negligeable compared to the benefits provided by energy savings."

"Damp spray cellulose insulation should only be used in wall assemblies that are able to dry towards the interior or exterior of a wall assembly, a vapor diffusion retarder should not be installed on the interior."

From my own research, damp spray cellulose has a higher r factor than fiberglass, fills the voids better, stops air infiltration better, and costs about 20% more than fiberglass. Spray foam costs about %50 more.

[dallasbill]

Insulating Concrete Forms -- poured concrete walls.

See: http://www.concrete-home.com/

[uktra]

Pstudent---The idea of thermos bottle homes with mechanical ventilation IS the credo of All building scientists. Very tight houses are need for energy effeciency and indoor air quality. Mechanical ventilation is needed for ANY house for proper ventilation.

[pstu]

Wish I'd phrased that differently, Uktra. Thanks for pointing out my inconsistency. Now I wish I had not called certain people "Building Science Experts". Instead, these are people who consider *themselves* gurus, have long experience and honest good intentions. However they spread mis-information through their own ignorance sometimes, and do not accept some of the principles such as "Build it tight and ventilate it right" (Lstiburek as I remember).

If I said there are experienced and well intentioned local "gurus" who cling to ideas at odds with Lstiburek, would that be more satisfactory to you? I want to listen carefully and honestly whenever I hear ideas from such a person, which clash with main Building Science conventional wisdom. Most of the time they will be wrong... but if they are ever right, I don't want to be guilty of a closed mind if/when they speak the truth.

There are a couple of issues which I consider worth debating, even if one of the sides is counter to Lstiburek. Fair enough?

Best wishes -- P.Student

[uktra]

Fair enough--but who ever contradics Dr. Lstiburek better know his stuff--I have studied under the man and I can tell you for sure, he knows more about building better homes, than any one I know.

[Edited by uktra on 03-17-2005 at 02:17 PM]

[energy_rater_La]

"Build it tight and ventilate it right"
Guilty.

Believe this very strongly.

Will keep believing it as I know it to be true
until I am proven otherwise.
I am, as always, willing to be educated.
There is ALWAYS more to learn.

But after several years of hit and miss of
weatherization and band aid fixes this
build it tight is working well for new homes.

Going back to existing homes for the same
sealing is a challenge, but reducing the
air infiltration is the first step to
savings, health and comfort in these homes.

[l•k]

oops

please delete

[Edited by l•k on 08-17-2006 at 11:15 AM]

[royc]

http://www.monolithic.com/plan_design/rfairy/index.html




Roy

[JBF]

Originally posted by pstu
You might think about this: Cellulose based insulation is going to be permeated with borax or some kind of insect poison. Cellulose is going to disintegrate into dust after enough years, and some of that dust is sure to get into the house. For this reason a Houston local builder who has a radio show (Tom Tynan) insists he will never put cellulose insulation into a house he builds. He thinks in a few years there will be a whole remediation industry devoted to sucking that material out of houses. Is he right? I cannot say. Just something to think about.

-- P.Student



It is treated with boric acid, which is non-toxic to humans. Boric acid is toxic to insects and is a fire-retardent.

[cem-bsee]

My house in Marion IN probably still has fiberglass under 6" cellulose which I installed about 1967 -- no complaints for about 30y while house was owned by my stepdaughter for the last 10y --
BTW, I have a 1898 newspaper which was just kept in a cardboard box for 50y that I know of -- not very brittle, not very yellow -- has wedding announcement for Mom's parents!

cellulose is just ground- up newspaper with boron added --

[JBF]

In 1976 I blew in 14 bales of cellulose over 3 inches of rock wool. The electric bill took a nose dive.

The electric company came out to check the system. They checked the meter and cut the wire tag and replaced it with a lock.

They came out again the next month. This time they replaced the meter and installed a bigger lock.

It was funny then but absolutely necessary now.

I'm in a new house. I'm in the process of replacing all my ductwork, adding a foil radiant barrier, installing eave and ridge vents, solar screens, and a ground-source heat pump.

I hope they come again.

[energy_rater_La]

JBF, you must be building in a climate like mine
with high temps in the summer.
I just wanted to let you know, and this is off topic guys,
please bear with me.... that in place of a solar screen
a window with a low e coating is your best investment.
The numbers you want to use to shop are these
at LEAST .4 U-factor, and a .4 shgc ( solar heat gain
coefficient ) these windows reflect heat out of the house
a must for a cooling climate.
good choice on the radiant barrier. excellent payback in summer, little to no benefit in winter months.
also the gshp is a good investment.
Ok back on topic now...

there were several things that struck me when reading
through this thread.

Tynan & his logic.. don't catch his show.

but this:
So, by that same causal logic, if he told you that you only needed a seer 8 A/C in Houston, and radiant barriers are a waste of money, you buy it. Except nowadays he advocates seer 12-13, strongly recommends radiant barriers in the attic, and as I said before: no longer slams ICF.

A leak in any attic duct will suck up dust -- it's there in spades in any attic, esp. an unsealed one! It has nothing to do with cellulose.

_____________________________________
so nowdays he is an advocate of 13 seer...the lowest
efficient unit legally produced anymore???
why not advocate 14 seer, 15 seer??
come on...let's do it right!!!

it is not only duct leakage that will suck dust (& the
fine powder of cellulose) but any unsealed area in to the
house. recessed lights are the worst...if they are not
air tight when the mechanicals kick on, they pull what will
fit through the holes in the housing ( insulation particles, dust, and the killer in hot & humid climates-
ambient & attic air, 140 degrees here in Louisiana with humidity of 80-90%...)
oversized cuts for stove vents, bath vent fans, duct leakage, all contribute to poor indoor air quality,
mold growth, sickness of family living in the home...the list is mind boggling.

btw any of you ever hear the housewife complain about having to dust so much?? chances are cellulose is in the attic, and entering through these leakage areas.
there has to be a hole, be it in the ductwork, plenum,
return air, or these oversized cuts & can lights.
In older homes the dust has built up in the attics &
is really dust, but the solution is the same.

if you see light from the attic from the conditioned space, it needs to be sealed. I test with a blower door
which is very helpful to determine these leakage areas.
and believe me, you always learn on these older homes.
( and for me on new homes also, but its a sad day
in my pov when I don't learn something..even if I forget it later!!!)

I do think that a denser insulation would perform better
& with cellulose you get a lot of dust. And little weight
for the density that provides a better performance.
but I don't advocate foam insulation. Based on personal experience of installs, which --suprise suprise-- the state backed me up on, the performance when tested,cost & TRUE payback, the cost which I think will come down in a few years. And in these few years the installs will (hopefully!) improve. Again hopefully the people who bought in to the 20K package will educate them selves
& THEIR EMPLOYEES to achieve the performance that is promised to the home owner...
When I test with a smoke bomb & pressureize the house..
the smoke pouring out of those ' unvented ' attics tells
the true tale...

Ok getting of the foam rant now. didn't really want to
go there.

Now pstu,
are you refering to Jim Bower's book?
what a good read! the thing I liked about it is that
he was a home inspector for years, and then bought a
sick house, and got sick. so he learned why.
I'm not a big fan of someone who bases their info on
stats & has no 'hands on'.

I also have Healthy House Inst.'s book
about how to build one, fix one & so on.
also a good read.

I am a fan of Joe Lstiburek, and have attended the
classes he gave in my hurricane recovering state.
just cause I have to say this..when I first met Joe
he was pushing foam insulation big time. I asked him if
Icynene was his middle name. these last classes no mention
of foam was made, and of course I had to ask him why.
Seems that they got into some 'problems' with foam in
one of the states..carolina..virginia???can't recall.
My understanding is that the wooden floors buckled
(house on piers), and other issues...where is that miracle
cure, fix all problems salesman now???
goes to show we all live & learn!!

my studies& testing show that it looses what sealing properties
it had over time, due to expansion & contraction of the
surface it was once attached to..(ok no more!!)

I had to laugh when I read the quote of Joe's, knew it was
him before I read the source.

I hope that DallasBill will continue to post, you make me
ask more questions pstu..thanks...I think.
and DB has great information, I enjoy both of your input
and if the discussions get heated, y'all just cool off
& continue. After all its all about learning, exchanging
info & ideas isn't it?

My pov is that with cellulose you have to have as close
as possible to complete air barrier between the attic
& conditioned space. then insulation type is a non issue
& install of insulation becomes the issue.

hope you will all have a great & safe weekend.

[mosestr]

So let me clarify...what do you all think about cellulose and fiberglass insulation. (LOL)

Remember...Sean Hannity..Rush Limbaugh...and Al Franken all have radio shows too. Do you believe or agree with everything they say?

Tom Tynan is just one man....one opinion. If you listen to his show, there is obviously something that you like about it. Don't give us that mess about you hate it, yet you can tell me about every caller and every answer given. If you hate or think he is just a mouth piece then turn the station!

gotta go to sleep, the show starts at 8am tomorrow!!!

PS. I am starting a cellulose remediation company.

[cem-bsee]

go back to the basics:
insulation is achieved by having LOTS of SMALL voids thru which no conduction takes place.

small particles of solid materials are not good for animal airways! eg: coal [black lung], asbestos, fiberglass, pressure treated lumber dust, grainery dust, . . . .

but then, there was a newspaper ~1948 article about a rattlesnake biting a man in TX & the snake died -- from arsenic poisioning -- man worked in arsenic processing plant & had lots of arsenic in his blood --

I have never hearh of anyone becoming sick from handling newspaper -- my Father, a pedetrician, stated that when doing Internship in Chicago [late 1930s], they frequently used newspaper under a delivering woman because it would be the cleanest thing available!

remember, loose installed insulations WILL settle! voids left because of sloppy fiberglass batt installs in studs most often causes 20% insulation LOSS!!! even small cracks have enormous affect. Then couple those losses with the heat transmitted through the studs --

The last I heard, the binders for fiberglass batts are flamable -- probably the worst item is the vapor barrier-- is it borax treated?

BTW, ICF to some means having a layer of foam board encased within the concrete slab | wall | roof.

The first attic insulation installed in our house was recycled asbestos fibers from a Colonial Bread oven in St Louis in 1947. Carried there in a bushel basket. Poor Jim died sometime after the age of 60 [I never really kept track.] I helped with that installation. Damm, I may die sometime soon! -- it will be sometime after the age of 73!

some humans are allergic to about anything -- I pull up poision ivy with my bare hands -- just wash with soap & water afterwards --

I suspect that cellulose is a mixture by weight of 85% paper & 15% borax solution -- maybe I will stop by a Cellulose insulation factory.

info from mfgr web:
GreenFiber has a comprehensive testing program to ensure that GreenFiber product meets the highest quality and safety standards in the industry. These standards are based on the current ASTM C739 “Standard for Cellulosic Fiber Loose-Fill Thermal Insulation”, and the amended CPSC Standard, 16 CFR Part 1209. These specifications cover the composition and physical requirements of chemically treated, cellulosic fiber, loose-fill thermal insulation for use in attics or enclosed spaces in housing, and other framed buildings with the ambient temperature range from –45.6 to 90.0C (-50 to 194F) by pneumatic application.

There are no health concerns associated with GreenFiber product. According to our Material Safety Data Sheets, approved particulate masks and eye protection should be provided and worn to protect from nuisance dust.

A third party periodically calibrates all GreenFiber plant’s process scales. Quality process control testing is conducted every two hours during production by the QC Technician to assure all standards are met and the product meets the specifications set forth in the standard. The QC Technician randomly samples a recently produced insulation bag either taken from the line, a unit in the warehouse, or off a trailer. The sample is taken from the product that has been manufactured no more than one hour prior to sampling. Daily logs are maintained and reviewed by the plant manager.

Our independent testing laboratory is R&D Services, Cookeville, TN (931) 372-8871. They are NVLAP accredited.

[Edited by cem-bsee on 08-19-2006 at 08:45 AM]

[entropyknocks]

Here is what I judge to be an objective look at boric acid.
http://www.beyondpesticides.org/infoservices/pesticidefactsheets/leasttoxic/boricacid_borates_borax.htm

We have successfully used it in the past as a flea treatment in indoor carpets. As an insecticide, the boric acid crystals shred the insect's digestive system, so its toxicity to bugs doesn't correlate to toxicity in mammals. With the research we did on it before using it, we felt that it was the best thing to use and allow our (then) babies to crawl around on it. However, they were girls, so no testicular risk was involved. :P

[mark beiser]

As a person who works in attics on a daily basis, I HATE CELLULOSE INSULATION WITH A PASSION.
Loose fill cellulose is a dusty nasty mess.

We turn down jobs that involve changes to the duct system if there is cellulose insulation during hot weather. We will do them during cool weather, but we charge a lot extra.

[JBF]

Originally posted by entropyknocks
Here is what I judge to be an objective look at boric acid.
http://www.beyondpesticides.org/infoservices/pesticidefactsheets/leasttoxic/boricacid_borates_borax.htm

We have successfully used it in the past as a flea treatment in indoor carpets. As an insecticide, the boric acid crystals shred the insect's digestive system, so its toxicity to bugs doesn't correlate to toxicity in mammals. With the research we did on it before using it, we felt that it was the best thing to use and allow our (then) babies to crawl around on it. However, they were girls, so no testicular risk was involved. :P

That is a great link. A Boric acid solution has been used as an eye wash for generations. Worrying about the toxicity of cellulose insulation is absurd. Use a good respiration filter and forget about it.

I have installed fiberglass insulation and have experienced the cough and have felt the irritation in my lungs. I never had a similar experience with cellulose.

It is the fibers of asbestos and the fibers of fiberglass that cause lung cancer. They do not dissolve. They don't decompose. An ingestion of either fiber is permanent, unless you can cough them up, or the cilia in your lungs can work them into your digestive tract.

I worked with fiberglass and asbestos in my 20's. I am far more concerned about exposure to to those carcinogens than I ever was with boron-based chemicals.

[sneakysnake]

i put the cellulose in the walls upstairs and it saved my 25% on my heating. which i had no insulation in the walls and they are made of plaster.

[clzair]

I agree it's just nasty, not as nasty as old rock wool.
But there is a big difference in the ability of the cellulose to not transfer IR heat. Whereas fiberglass does transmit IR. So in certain roof insulation details it is a very big factor.
I don't have the info handy but if some one needs it I can hunt it up.

[swagging tool]

What a great thread the never ending debate over the best insulation. I have worked in all of them and of the 3 main fiberglass, foam and the BORAX coated newspapers (LOL) I still choose the newspapers. Cellulouse insulation is the best money spent for the amount of preformance of the three. It is dirty dusty and easy to loose tools in but for keeping that hot attic air from comming into the home it at the present time in my area it cant be beat. Just a side note Applegate insulation a large mfg. of cellulose insolation is located a couple of towns over from where I live I used to work for a company that did the maint on their heat and a/c equip. If you think it is dusty in an attic you oughta work on something in that plant I swear you could change the filters daily and they still would'nt show light through them. I left that company but I think they were about to put a water useing filter system (Self cleaning) on the office units arround that time. I know that some in here will say that foam will win hands down every time for r- value against cellolouse but I did state in my area meaning that the humidity problems we have with foam prevent us from spraying the cielings we have to spray the roofs from the undersides as well as the walls and seal everything tightly thus makeing the attic space a condidioned area. That is compleatly or partly temp humidity controled. This is quite expensive but makes for a well insulated home and for some really eyebrow raiseing heat load calculations. I once figgured an attic done in this fasion as a zone added to the main floor and it decreased the tonnage needed even though i had added 2400 sq feet more space the the equation. One other thing about foam is that it is not a good sound barrier and all homes done in this way have really pleasent sounding roofs when it rains. one other tip is to make sure you get the airhandler perfect in the attic if you use this method because any sounds it make will shoot right through just sheetrock wedges rubber pads and dampening tape are a must in theese installiations.