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Community and Q&A

Blown-in Fiberglass Insulation Escaping Through Vents

vikihymer60 | Posted in GBA Pro Help on

We have had fiberglass insulation contaminate our house. We know it entered through the air vent for the furnace and through poorly installed air vents to the house. We are in process of clean up so we can return to the house. I am still worried about the fiberglass insulation because I have had such a violent reaction to it. Is it possible for the insulation to escape out of the vent openings for the metal roof? All possible openings inside the house has been plugged, but am wondering about outside the house.

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  1. GBA Editor
    Martin Holladay | | #1

    I'm not quite sure what you mean by an "air vent for the furnace." I'm guessing that you are talking about insulation installed on your attic floor, but I'm not sure.

    If you are talking about insulation on your attic floor, it is conceivable that under a very unusual wind event -- something like a strong gale or hurricane -- wind pressure could move insulation fibers from your attic floor to your ridge vent or soffit vents. But that would be quite unusual.

  2. vikihymer60 | | #2

    Air vent to the furnace is the fresh air vent for the propane furnace to have air.
    Outside where the metal roof sits on top of eaves, there are openings for ventilation--no covers. Could the fiberglass escape there? What about negative air pressure in house? Would it cause the fiberglass to be "sucked" out when doors are opened to the house?

  3. GBA Editor
    Martin Holladay | | #3

    If I understand you correctly, you are saying that insulation fibers entered the burner of your propane furnace through the combustion air intake. That sounds unlikely. The combustion air intake pulls air from outdoors -- and there shouldn't be any insulation fibers outdoors. Once in the combustion chamber, these fibers would be burned, and any combustion byproducts would be expelled from the house through the flue.So the fibers couldn't enter your house that way.

    Maybe your forced-air distribution system has a fresh air intake as part of a supply ventilation system? If that's true, then the fibers might have entered your ductwork. But I still don't know why there would be insulation fibers outdoors near the intake grille.

    You wrote, "Outside where the metal roof sits on top of eaves, there are openings for ventilation--no covers." It sounds like you are either describing (a) soffit vents, or (b) the air channels under the ribs of the corrugated metal roofing.

    There is no reason to think that fiberglass fibers would "escape" through either opening, unless your house was exposed to a gale or a hurricane.

    If your house is under strong negative pressure, strange things can happen. You might want to hire a home performance contractor to make sure that your ventilation system is balanced.

  4. vikihymer60 | | #4

    Our fresh air intake is vented into the attic. Thanks so much for your input.
    Ok-what is a home performance contractory and how do I find one?

  5. GBA Editor
    Martin Holladay | | #5

    If the "fresh air intake" is the duct used to bring outdoor air to your forced-air ductwork (a type of ventilation system called a central-fan integrated supply ventilation system), it shouldn't be pulling air from your attic. It should be pulling air from a grille located on a side wall of your house.

    If you know the name of the contractor who installed the ventilation system, you should call them up and make them fix the error.

    The two organizations that certify home performance contractors (also known as energy raters) are RESNET and BPI. Follow the links on those words to find a home performance contractor in your area. (If you visit the RESNET site, click the tab at the top of the page labeled "Find a Professional.")

  6. user-945061 | | #6

    Martin - I'm pretty sure the owner is talking about combustion air ducted to a small enclosed utility room for an 80% or less furnace. We often see 2 ducts, one high and one low in the utility room walls. Usually these are a extended a few feet above the attic floor, but it's possible that the insulation contractor blew a little fiberglass into them.

    I usually try to eliminate them, either by upgrading the furnace to sealed combustion, or bringing combustion air from the remainder of the house. If the dhw is gas, this needs to be factored into the solution.

    I don't like fiberglass, but I'd be surprised if "violent reaction" and household evacuation wasn't overdoing it a bit. Makes me feel a bit mournful for Chopper Read.

  7. vikihymer60 | | #7

    The leaving the house was strongly suggested/required by environmentalist specialist as health care personal were coming into the house caring for my mom on hospice. The fiber count was 58-65 as compared to 1.0-4 for normal. The legality became an issue with hospice. The violent reaction was from only 2 hours sleep per night for six months and sores all over my body. Even doctors were remarking about the reaction. We lived in the high count for about 15 months before we realized what was happening. No one has heard of this before even the environmentalist. Most difficult to go through and with mom on hospice it all became a nightmare. Hopefully it is almost over. House is cleaned and holes plugged. I am just a bit concerned as doctors have warned me that I will most likely be super sensitive to the fiberglass from now on. Just needing advice, not judgment. Also need prayers.

  8. Aademrm | | #8

    I hope this reaches Viki somehow. I just lost my house and all of my clothes and furniture from attic insulation getting introduced into the living space through a leak in the ductwork. It made me very very very sick. I can’t be exposed to any amount of fiberglass, which actually can escape through attic vents or if the living space is open in any way to the attic. Negative pressure will pull it through dried out caulking. Missing grout, unsealed light fixtures, even outlets and switches. I have learned from building inspectors that sealing everything is imperative. I rarely come across anyone like me who is very highly sensitive to fiberglass. For me it triggers an autoimmune reaction that is beyond horrible to go through. I’m just throwing this out in the weird hope that Vicki or someone else with this problem reads this and responds.

    1. Amills93 | | #9

      Hey I believe this is what is going on in my house it is absolutely terrible and now at work (I'm a plumber and hvac tech) anytime I'm under a house or in an attic any fiberglass just tears me up and I'll have worse than normal symptoms for weeks but just being in my house my nose eyes and lungs are all effected you can see abnormal dust in vacuum filter on top of door jambs near receptacles and switches everywhere and anywhere I rent my home and don't know what to do because moving isn't really an option at the moment my landlord is a retard been telling her multiple times about it and her answer was to get air duct cleaning which did nothing really

  9. Jon_R | | #10

    > very highly sensitive to fiberglass

    Maybe you are reacting to the binder resin that coats the fibers? No doubt some people have strong reactions to things that don't bother most people.

    If there is a problem even with proper ventilation (outdoor intake, neutral or positive house pressure, lots of CFM), consider adding cellulose on top of attic fiberglass. Or maybe removing the fiberglass and using only cellulose in the attic.

  10. Expert Member
    BILL WICHERS | | #11

    I agree it’s probably the binders more than the fiberglass itself. Fiberglass is glass fibers — silica, basically. Silica is a pretty stable material so you shouldn’t have allergic reactions to it, since allergic reactions usually involve chemical interaction (ie some foreign compound triggers a response by the body).

    The glass fibers themselves are an irritant though, but a mechanical irritant — they basically poke you with tiny glass needles and make you itch. The fibers don’t dissolve in body fluids, which makes it bad to breath the dust since your body can’t break the material down. Dust precautions are important here.

    If you have a reaction to a home with fiberglass insulation in some closed-off area, you’re probably reacting to some compound — like a binding agent — that is offgassing. The other possibility is it’s not the fiberglass at all, but rather some foreign matter hidden in the insulation. Lots of critters burrow in fiberglass, so mouse pee or squirrel poo are big potential problems. Sometimes dead and rotting critters can be a problem too. Mold is another potential concern, and mold spores can certainly trigger allergic reactions in many people.


  11. Amills93 | | #12

    I used to not be bothered by fiberglass until I moved in to here and it wasn't until about 10-12 months of living here that we all started having issues skin discomfort and eye pain my 3 year old says his eyes hurt all the time and he will randomly have several bumps come up and complain of pain and I have a uv flashlight qnd you can sometimes see the fibers really well when they are on the bigger side.stomach issues is another one that everyone in my household now has pin discomfort trouble taking a shit. We have loose fill fiberglass in the attic with corrugated metal roof no plywood under it just attached to stud with no flashing anywhere no end caps nothing just metal there where only 2 rows of screws until u added alot more and silicone lots of silicone throughout the hole house we have a slum lord and their idea of mateinence is 2 crackheads with duct tape and flex seal there were large cracks everywhere above door jambs , crown molding, sheetrock the plumbing was terrible they didn't want to penetrate the roof with any plumbing vents so they just did away with them who needs em anyway but as a young family struggling to get by especially now more than ever moving is not really an option at the moment and rent just seems to continue to rise house I seen last year for 800-900 are around 1200 we feel stuck and feel like bad parents having 2 young children having to live there I'm to the point that I'm ready to take legal action but don't know what grounds I have and what is or isn't my responsibility. It's been a horrible experience

    1. Expert Member
      BILL WICHERS | | #13

      Fiberglass is an irritant that tends to make things itch, but it doesn't usually cause any issues unless it's disturbed. This basically means it stays put unless you work with it and move it around -- it won't "leak" through cracks after it's settled. The usual things that happen are skin irritation (itchiness, but no rash-like bumps), and cough if you breath the fibers. I suppose it could cause eye irritation too, but that's not what I usually see myself. Since I always wear a mask, skin itchiness is all I get. Taking a series of cold, then hot, then cold again showers helps to get the fibers out of any pores in your skin.

      If you're feeling sick, I doubt very much it's the fiberglass itself. What I would suspect is either mold or animal feces (poo), or some similar biological contaminant. This kind of thing most certainly CAN make you sick, and it CAN leak through cracks and float around in the air on it's own. There are enviornmental testing companies that can take air samples to check for this sort of thing. Testing is usually a few hundred bucks or so.

      Leaking sewer gas can also make you feel sick, but you'll usually smell it -- it smells like a nasty toilet that has been used for several days over and over again without getting flushed. use of AAVs (Air Admittance Valves) is permissible in place of "real" plumbing vents in some places, but not all, but you still need at least ONE functioning "real" plumbing vent to the outdoors in the system somewhere. Those vents can sometimes get plugged up by critters, so that might be something to check.

      Another thing that can make you feel sick, usually with a headache, is elevated carbon monoxide levels. THIS IS VERY DANGEROUS. This issue is usually due to either worn out or improperly vented combustion appliances, typically gas fired water heaters and furnaces/boilers. I recommend you get a carbon monoxide detector/alarm and install it as directed (they are inexpensive devices available at all the box stores, and they can save your life). I highly recommend installing at least one of these (I have two in my own home) regardless of what your actual issue is, since they are valuable safety devices.

      Again, I think you have issues here other than the fiberglass. It's worth checking things out. Animals in the attic can cause a lot of problems, even if they aren't there anymore, so look for signs of staining on the upper floor sealing (this is a sign of animal urine in the attic), and if you go up in the attic and see lots of black mold or animal poo (or even dead animals), that's another problem.

      Regarding the landlord's responsibility to clear any of these issues, that would be a question for a lawyer and would probably depend on the wording of your lease.

      I hope you're able to get some relief. I recommend ventilating your home with fresh air as much as you can in the interim to help reduce the concentration of whatever is in the indoor air that is bothering you. If you have a forced air furnace, I'd check the filter too to see if anything is growing on it.


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