Cellulose Insul Destroys Wire and Pipe??
Thumbsmasher
| Posted in Energy, Heating & Insulation on
I’m getting ready to insulate my house, and I’m planning to use blow-in cellulose insulation. However, I was just told by an insulation contractor that the borax/boric acid used to fireproof the material is corosive to electical wires and plumbing.
I’ve never heard of this anywhere, but this guy was adamant. He said that this was made evident to him when some guys screwed up mixing up a batch of insulation and put way to much borax/boric acid in it. He said the wires and pipes coroded in only a few months and the drywall had to be ripped off and everything replaced.
Granted this guy was trying to sell me on fiberglass batt insulation, but I’d like to investigate this claim. Has anyone ever heard of this before?
Thanks for the help
Replies
Sounds like a case of mega BS to me.
Some problems were reported in the 70's when there was huge growth in the industry and no corrosion standards in place.
I don't think there's any issue today.
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
A legitimate argument for fiberglass batts over blown in is that the batts are relatively easy to pick up and put aside if you ever do any more work on the house, while the blown in stuff is a mess forever.
-- J.S.
John: Especially if you spring (or is it sprung, for the past perfect subjunctive actice case?) a leak and water drips into the cels for a week before you find it!
DonThe GlassMasterworks - If it scratches, I etch it!
Thumb, This story is way beyond BS.
He said that this was made evident to him when some guys screwed up mixing up a batch of insulation and put way to much borax/boric acid in it.
Is this guy grinding his own newspapers too?
It's not make your own stuff, you buy it ready to blow. This guy is selling fiberglass and hot air.
Joe H
A boric acid solution would be corrosive to steel and I would guess it would also be corrosive to bare copper. I have heard that cellulose insulation treated with boric acid can attack light gauge steel framing members, particularly where the insulation was in contact with steel framing members that periodically were coated with condensation. I have no idea how much of a problem this is in actual practice. I would guess that the coating/insulation on electrical wire would not allow the boric acid to come in contact with the copper wire. On pipe, I would guess there might be some corrosion if the pipe, particulary black pipe, were in a situation where it sweated.
(Disclaimer: this is basically speculation on my part as I have not actually witnessed any situation where borate treated materials were in contact with steel or copper...)-
There were some claimns years ago that truss connectors had been (could be?) damaged by cellulose when dampened - but those reports have never been verified so far as I've been able to find (and I've looked.)
_______________________
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
I've looked on the internet and couldn't find anything that said there was a problem with borate treated insulation and light gauge steel framing. There was a lot of coverage of a nuclear reactor where boric acid had eaten through some thick steel lining in relatively short order, but I didn't read the reports so don't know what the other conditions were. Thus the reason for my disclaimer... However, acids will attack metals, so I have to assume that if there is an aqueous boric acid solution on steel, it would cause some degree of corrosion. But how much (or how little), I have no idea.
A couple of hits from google using "cellulose insulation corrosion":
Some background:
http://www.regalind.com/metalbuildings.htm
And, probably the most famous (infamous?) case:
http://www.chemaxx.com/cellulose.html
I recommend cellulose.
Mongo - interesting site with the "case study." I wish he had given particulars - especially when the house was being built and if any attempt was made to determine whether the cellulose insulation which was installed met the various standards for cells.
Some info on the water problems would have been helpful too.
_______________________
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
Bob,
I recall the 'case study' house being discussed more in-depth in ohter articles. There indeed was a problem with the cellulose, but I can't recall what it was. For some reason I want to say that it was either from a fringe manufacturer, or that the installer added too much water to it during the installation using a wet-spray method. I thought there were problems with the house as well, in terms of moisture, mostly with flashing, and that it was mostly the excessive moisture used in the installation followed by wetness from poor construction that set the whole shebang off.
Edit: I found this link...a few more detaile in the house:
http://www.constructiondefects.com/pr_a_forowners.asp
Not a happy ending.
Edited 11/5/2003 4:01:52 PM ET by Mongo
Mongo -thanks for that link,
One thing I don't get - the articles suggest that there was too much chemicals added which leeched into the wood and fasteners damaging them, AND that there was a lot of mold.
I thought many of the fire retardent chemicals also are mold growth inhibitors (especally the borax based chems) but maybe not.
_______________________
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
I glanced through the article again and didn't catch a reference to mold.
When I first heard about this years ago, I thought the insulation was wet-sprayed and the drywall was put up almost immediately.
Too much water was used in the spraying of the cells and the drywall started looking a bit funky.
Things came to a screeching halt and the house sat.
Then water problems began in ernest, infiultration from outside, and, apparently, leaks from inside the walls.
I never did hear the final outcome, if any settlement occured that eventually allowed the house to either be repaired of razed.
Thanks for the links. I guess cellulose doesn't look too bad from a corrosive standpoint when the manufacturer incorporates the proper fire retardants. I notice that on the Regalind link that you gave that it discusses "borates" but not "boric acid". I am still of the opinion that boric acid is corrosive to copper and steel (other than certain stainless steels), however, it may not be a particularly strong corrosive. As I mentioned, about the only thing I found discussing corrosive effects on steel of boric acid was in regard to what may be a rather extreme situation in nuclear reactors. However, a number of sites specifically mention that their stainless steels are resistant to boric acid corrosion in a way which seems to indicate that regular steels are affected by boric acid. The chart at
http://www.srcoils.com/corros.html
indicates that boric acid is corrosive to steel and copper, but doesn't indicate the strength of the effect. Perhaps the zinc on light gauge steel framing members is sufficent to protect those members during their lifetime in typical service. Unfortunately, the web does not always provide the ultimate answer...
It's interesting when you pay attention to what is and isn't written.
When I was looking through the hits on that google search, I found interesting ommissions or word choices on the part of some cells companies, as well as on the sites of some of the FG companies.
Potato, po-tah-toe...
Seems to me that limiting the moisture it the larger answer but IMHO a simple coat of inexpensive paint would likely provide substantial protection from any detrimental electro-chemical interaction as long as the moisture exposure was limited in duration. I would think that a case of $2 a can spray paint, color coordination optional, would protect any truss connectors or hurricane straps.
A persistent roof or plumbing leak, if it goes undetected and uncorrected tosses this into a different category as a clear building defect.
I think wiring would be less a problem as long as Romex or NM conduit was used. The plastic would, IMHO, protect the conductors. Metallic conduit , particularly if a conduit ground is used, could be more of a problem. Metallic sheathed cables such a MC or AC would also suffer.
The GEC, Grounding Electrode Conductor, is commonly bare copper but insulated or covered versions are allowed and easily available. In this context they would make sense.
How many billion bags of the cellulose insulation sold from 1980 to now.
I have not heard of any class action lawsuits on cellulose insulation companies for the corrosion problems. Have you?
"There were some claimns years ago that truss connectors had been (could be?) damaged by cellulose when dampened..."
That's the first I've ever heard of that.
The only thing I've heard for sure is corrosive to truss plates is the fumes from hog manure.My memory isn't as sharp as it used to be.And my memory isn't as sharp as it used to be, either.
Boss Hog -
I don't know the source, but the "concept" made the HI rounds 8-10 years ago.
Hog manure fumes? Hmmmm.
Think I'll let it go {G}
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Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
Bob: I sprung (or is it sprang?) a leak in the ceiling over my LR. Water dripped into blown in cels for at least a week before it found a way down a DW screw and announced its presence. My ceiling trusses had at least 4 joints get wet and stay wet for a week. Not at home now, but will make it a point to look at the galvanized connector plates when I do and give you (and Boss Hog) a current data point on what happens. We plan to leave the 3X6 ft opening that way for several weeks to ensure everything thoroughly dries out. I was more concerned about the 4X2's drying out to prevent mold growing in the bottom chords than I was about corrosion. The water wicked along between the truss members and the sheetrock, so the trusses were pretty waterlogged along the surface. They had also turned black & slimy in a few spots. We are in no hurry at this point.
DonThe GlassMasterworks - If it scratches, I etch it!
Don,
Be looking forward to your info.
(I almost said "Great! - but, obviously, that would have been along the lines of "Aside from that Mrs Lincoln, how did you enjoy the play?" {G})
_______________________
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
Crawling through attics I have sometimes noticed some, not a lot,of light corrosion on metal parts exposed to cellulose insulation but the effect seems limited to areas that have moisture problems which makes me unsure if the corrosion might not have happened anyway. I have not seen any corrosion in areas not having both moisture, at least occasional, and insulation.
I have also seen some corrosion, a bit less I estimate, associated with fiberglass insulation. I'm not sure any difference is not more associated with cellulose's water holding tenancies not the boric acid based fireproofing.
I think this is more a warning to control moisture than a bash against cellulose. Things, IMHO, were simpler when there was little or no insulation or vapor barriers. Walls and attics were allowed to breath. Of course the occupants stopped breathing when they got their power bill so that method was not without compromises.
Edit for spelling.
Edited 11/5/2003 12:12:06 AM ET by 4Lorn1
"...corrosive to electrical wires..."?
Better not be any bare conductors in there regardless of insulation chosen.
I have seen bare copper grounding conductors in a number of situations which I always assumed was code compliant at the time they were installed, so would appreciate your updating me here. The most common is for a bare grounding conductor to go through a wall from the main electrical breaker panel to an outside ground rod. I have also seen a number of bare ground wires from electric ranges back to the main panel and also from the main panel to bond water pipes and steel building members that need to bonded. I have also seen descriptions of how to place bare copper wire in footings to use as the grounding point and I assumed that these would come up through the wall to the main panel as bare wire without going through conduit. The other situation is that there are a couple of descriptions on electrical web sites which describe how to retrofit old two wire wiring outlets with a copper wire run back to the main panel. I assumed that these could be bare copper.
i think the distinction should be drawn here about the fire retardants most commonly found in cellulose. there are two types. one is the mixture of boron and boric acid. the other is ammonium sulfate. wet-spray cellulose with high levels of ammonium sulfate in it and you are begging for problems, as it is well known to be corrosive when mixed with water. this fire retardant is much less costly to the manufacturer than boron and is used in cellulose which is slated to be dry- blown into attics or dry-packed into walls. any manufacturer worth their salt will clearly mark these bags "not for wet-spray application", although i have run into ammonium sulfate material which was not marked accordingly. i have seen no problems associated with ammonium sulfate cellulose as long as it's installed dry and kept dry, but i also live in a semi-arid climate. it would be interesting to see a study done with ammonium sulfate cellulose which is dry-blown, but in more humid climates, although i suspect that with proper ventilation, corrosion problems would be non-existent. boron-based cellulose, on the other hand, is not considered corrosive in wet-spray applications, except where 1. too much water is used to make the cellulose stick to a wall. this is a sure sign of an inexperienced installer, since one way to make it-stick-no-matter-what is to just use more and more water. then it takes forever to dry and by that time you may get some corrosion, mainly because you have just soaked everything that's metal with a bunch of water that's going to be there for a while. if you can grab a handful of cellulose and squeeze even a drop of water out of it, it's too wet. 2. the wall gets a poly film applied before the cellulose is allowed to dry completely. same effect- after a while, the water will start to corrode stuff. this is all-too common for builders on a tight schedule. ("get that poly on the walls so the rockers can get in here!".) if wet-sprayed cellulose jobs are done correctly, you can expect a superior result from this process in terms of air-tightness, comfort level and lowered heating and cooling costs, but get some references and check them out thoroughly. as with any construction trade, the insulation industry has it's fair share of hip-shootin' yayhoo's, much like that first guy you talked to. therm
Very informative post. Makes sense. Fits well with what I've seen.
No criticism of the post itself but would you please break up those blocks of text. Just hit 'Enter' every nine or so lines. Makes reading the post much easier for tired eyes. A small point that makes a big difference. Thanks in advance.
Thanks for the info. Seems very informative.
Not to challange you, because what you said and the way you said it has the ring of authenticity and authority, but could you let us know the basis for your knowledge?
As a home inspector, I like to know the sources for the information I get to have some basis on which to use it and pass it along.
Thanks.
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Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
sorry about the lack of background. i'm an insulation contractor in colorado, in business about 22 years, specializing in re- insulation of existing structures, as well as new home insulation.
i started college in solar technology and heat transfer systems, then switched to the insulation side in order to concentrate on making solar and conventional heating systems as efficient as possible thru the use of high- performance insulation procedures.
as time went on, i had heard so many statements and stories about this insulation or that insulation that simply didn't have the ring of truth to it. for many years, i have done my own testing and research, as well as consulting with manufacturers of cellulose, fiberglass and rockwool products. other research has included finding studies done by laboratories, government entities and universities in order to get an un-biased feel for what is fact and what is fiction. ( i have heard a lot of fiction, even from people in my own industry!)
i admit to a distinct bias toward the use of cellulose insulation in many instances, as i have had the best results from it in terms of sealing against air infiltration as well as high- level thermal performance. that being said, materials like fiberglass, rockwool and cotton batt insulation also have their place and we use them accordingly.
my goal is to be able to answer someone's questions and know that it's an honest answer based on the facts as i know them. thanks for asking, bob...... therm
Thanks for the info -very impressive resume.
And welcome to the forum - I hope you'll stick around, authoratative sources of information are indeed very welcome and appreciated!
_______________________
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
thanks for the welcome, bob, and everyone else, looking forward participating in this forum. therm
Alright, welcome also, I'm relatively new to this forum too and have been looking for input on blown cellulose and vapour retarders...I am renovating an 80 year old school house, brick veneer with balloon-framed 2x4 walls sheathed on both sides with 1" half lap boards faced on the exterior with tar paper and interior strapped and then lathe and plaster. I have stripped the interior walls to the lathe and am considering where to from here.
Planning to insulate with cellulose, not planning on removing interior planking, should I install poly on boards? over lathe? no poly and seal openings, edges etc. and paint with vapour diffusion retarder paint?
Much of the input so far has pointed to a poly VDR, but others do feel that reducing air movement from interior to envelope would be effective (easier for me) and allow the building to breathe since it can't be rebuilt with the proper integration of air barrier and VDR. Anyone with thoughts/experience about VDR paints or paint as a VDR?
Thanks for any input, also, as an installer what are your thoughts re: DIY installation?
Suggestions:
Look for evidence of moisture on the backside of the sheathing. Pay careful attention to areas around window and door openings. Before insulating, you want to make sure everything is dry, and is going to stay that way. May be worth removing lathe too for better visibility. Brick veneer can make for tricky water issues. When you say "veneer", is the brick original fullsize brick, or was it faux brick applied over the original lap siding?
In most climates, studies suggest that vapor barriers may cause more moisture problems than they solve. Search around the web for info on "Airtight Drywall", or "Airtight Drywall Approach".
the tar paper on the exterior will act as a vapor barrier on the outside. to add another one on the inside will create a double-vapor barrier with insulation "trapped" in between. even this is generally not a problem if moisture in large quantities is never introduced into the walls, ie rain water entering thru the top of the wall,etc.
vapor from the inside of the house travels along with heat loss thru the walls. hence, if a house has no wall insulation, vapor will travel thru the wall hitching a ride with the heat loss. however, once a wall is insulated, the heat loss is reduced to roughly 1/5 of what it was before, and the moisture able to travel thru is also greatly reduced.
cellulose has an innate ability to absorb, then release moisture provided that moisture has an escape route, or can leave the same way it got in. in your case, i would leave off the vapor barrier on the interior side, then in terms of the vapor barrier paint, it's really a personal preference. some folks feel more comfortable using it, but with primer and the state of latex paints these days, you would have a sufficient vapor barrier that could still breath a little, and that is the escape route.
since you have a balloon frame, dont forget to stuff fiberglass into the top and the bottom of the wall! people forget that one a lot. if you go the diy route, i would figure up the bags of insulation required for your job, the estimated time involved, and compare that to what a contractor would charge. i think one advantage to using a contractor, especially for wall insulation, is that the insulation machines we use are better at packing a wall with cellulose than, say, a loaner from a lumber yard. a contractor also has to warrant the job against defective workmanship, settling, etc. the key here is to make certain the walls get well- packed, as it ensures they will never settle, and air cannot penetrate a densly packed cellulose wall.
if you get a chance, let me know how it turns out..... therm
Ditto what Bob said -
Glad ta have ya here, and I hope you'll stick around.There is a great man who makes every man feel small. But the really great man is the man who makes every man feel great. [Chinese proverb]
thanks a lot... hope i can be of service and learn some more along the way. therm
Absolute hogwash - nothing but
We do wet-blown applications where it’s being sprayed directly onto sheet metal, steel, wood, etc & the cellulose we use will not mold or corrode or rust. It’s primary use is sprayed onto metal