UFFI recognition & identification in buildings.

This article illustrates and describes UFFI - urea formaldehyde foam building insulation and describes where it is found, when it was used in buildings, how to look for it, how to distinguish this from other building foam insulation products, and its health effects.

We include identification photographs and a description of a very simple field test that can easily distinguish between 1970's vintage sprayed or pumped UFFI insulation and more contemporary icynene or polyurethane spray foam insulation jobs.

Our page top photo illustrates that depending on its environment, history, and formula mixture at the time of installation, UFFI may vary in color from orange-tan to bright white.

UFFI Insulation - What Was the Urea Formaldehyde Insulation Worry

This photo shows that in this building there has been a series of insulation retrofit projects using different insulation products. In the center of the photo we see pink fiberglass insulating batts.

Below the fiberglass insulation we see blown-in loose-fill cellulose insulation.

And in the foreground (and under our © notice) we see a crumbly, cracked slab of UFFI foam insulation as well.

UFFI or Urea Formaldehyde Foam Insulation was an insulation retrofit product used in the 1970's. This expanding foam insulation was mixed on-site and then pumped into building wall or other cavities in older buildings which were not previously insulated.

For a time some consumers were concerned about a possible health hazard from formaldehyde outgassing that might have occurred during the curing phase of this insulating product in some installations, particularly if the UFFI was improperly mixed.

Article Contents

• UFFI in BUILDINGS, SUMMARY
• SHOULD YOU AVOID BUYING a UFFI-INSULATED HOME?
• UFFI, HOW TO SPOT A RETROFIT INSULATION JOB
• UFFI, EXTERIOR INSTALLATION SIGNS
• UFFI REMOVAL PARTICLE SIZE HAZARDS
• UFFI SHRINKAGE LEAK IMPACT CALCULATION
• UFFI HAZARD HEALTH CANADA STATEMENT
• UFFI HAZARD RESEARCH Dust, Formaldehyde offgassing

UFFI In Buildings: A Summary of What You Need to Know

Our photo (below left) illustrates that even when there is no evidence of a UFFI retrofit from outside the building (wall plugs) nor inside the building (wall plugs in the occupied space or attic stair walls), a thorough inspection of rarely-entered (tight) attic or crawl space areas can discover UFFI that exuded into the space when it was pumped into the building walls.

The photograph shows UFFI as it was found in a small attic crawl area in a New York home during a 2008 inspection. We estimate that the home, built perhaps in the 1940's, had been insulated with UFFI in the 1970's.

Color of UFFI Insulation

Interesting in this image is that the characteristic yellow-gold skin color of the UFFI sprayed foam insulation is not always present, and a second slab of UFFI was stark white.

Early cancer research on UFFI

Some earlier research on the carcinogenic effect (cancer causing) of urea formaldehyde foam insulation suggested that formaldehyde out gassing from the insulation formed a significant cancer risk.

Eventually, additional study suggested that the initial cancer risk from formaldehyde was not supported, at least in this application.

The level of formaldehyde that out gassed f

rom UFFI depended in part on how the foam product was mixed at the site, and not all building insulation projects using this substance produced the same level of formaldehyde.

The level of outgassing formaldehyde from UFFI insulation declined steadily with age. This was an open-cell foam that did not retain its gases long term.

No formaldehyde outgassing found after the foam aged.

More interesting was the observation that perhaps largely because this insulation formed an open-celled foam, even if there were high initial formaldehyde out gassing levels, after months or at most a few years, even careful measurements were unable to detect any levels of ongoing formaldehyde out gassing from this material.

Only people hypersensitive to chemicals 

such as sufferers of MCS (multiple chemical sensitivity) and some people with other respiratory illnesses seem to have any remaining reaction to this material, and even in that case a study of such reactions is complicated by the observation that higher levels of formaldehyde out gassing from building products occurs from some furniture padding and from some glues or finishes used in chipboard based cabinets or sub flooring.

Yet at the peak of the UFFI enviro-scare, and exacerbated by inconsistent advice offered by government and private health experts, some buildings were sold at a significant discount to allow for extensive gutting, cleaning, and re-insulating of building cavities.

See also UFFI HAZARD RESEARCH Dust, Formaldehyde offgassing

Should You Avoid Buying a UFFI-Insulated Building? Conflicting answers from the U.S. CPSC

The short answer is no, in our opinion, but there may be some insulating defects (such as shrinkage) and a modest resale impact to consider.

Bottom line: confusion among home owners and buyers who considered whether or not UFFI should be considered a problem in homes originated in a formaldehyde offgassing problem that occurred in some UFFI installations, principally due to improper ingredient mix, exacerbated by conflicting opinions offered to consumers by the U.S. CPSC.

In the 1970's we made three successive telephone calls to the US CPSC to inquire about the hazards of UFFI in a home we were evaluating. Because UFFI is an open-cell foam product, even if excessive formaldehyde was present early in the insulation's life, it off-gassed rapidly.

It is highly unlikely that today you will detect formaldehyde offgassing from insulation retrofits performed in the 1970's and 80's. However there may be high indoor formaldehyde levels from other sources such as particle board or Chinese laminate flooring.

Today most experts agree that unless there are other related problems such as water leaks into the insulated cavities, UFFI in buildings is not a health hazard.

Range of "Expert" Advice on Buying a Home with UFFI is contradictory

However back in the 1970's we received these four different answers from three different people answering the CPSC UFFI hotline on the same day:

1. Do not buy the home under any circumstances. The cost to remove the UFFI and clean the wall cavities will be greater than the value of the home.
2. Buy the home but remove the UFFI insulation. The remaining scraps in the wall cavities will be insignificant as a formaldehyde source.
3. Buy the home and don't do anything about the insulation: the health hazards have been exaggerated and are probably very low if any.
   
   Today, in 2008, we add an updated opinion:
4. Don't refuse to buy a home because of the presence of UFFI in its walls or ceilings;
   • purchase some test kits and actually measure the formaldehyde level;
   • realize that the foam is open-celled and that all of the formaldehyde will leave the building;
   • if the insulation was added more than five years ago there is almost no chance that you will detect any formaldehyde from the insulation;
   • any remaining formaldehyde problems will probably be from other sources such as carpet padding or some composition wood-product building materials like chipboard shelving.
   • examine the insulation in wall cavities to see if UFFI shrinkage has left so many gaps that you need to improve the building insulation. Shrinkage of the insulation product produces openings which may permit significant air leakage or simply thermal bypass leaks, reducing the effectiveness of the insulation system - a problem referred to in the industry as thermal drift.
   • Realize that a few future buyers may have an irrational fear of the UFFI - a condition that might have a (probably small) impact on property resale - see Enviro-Scare, the Cycle of Public Fear

Inspecting several such projects it was interesting to note that the one real defect of this insulation product was that depending on how it was mixed, it shrank after installation, leaving gaps of no actual insulation at the top and sides of wall cavities - it wasn't the perfect insulating seal that was promised, but it was not the carcinogen that was feared. The shrinkage problem with UFFI is discussed

at UFFI SHRINKAGE, THERMAL BYPASS LEAKS.

Details about the possible impact of the presence of UFFI insulation in buildings on the sale price or time on market of a home or other building for sale are

at UFFI INSULATION IMPACT ON HOME SALE PRICE.

To consider other formaldehyde off gassing sources in buildings

see FORMALDEHYDE HAZARDS - home and also

see FORMALDEHYDE in LAMINATE FLOORING

Current Health Canada Statement on UFFI

UFFI, which is foamed in place and used to insulate buildings, has been banned in Canada under the Hazardous Products Act (HPA) since December 1980.

UFFI was banned due to the high levels of formaldehyde that were given off during the installation process, as well as the continued off-gassing of formaldehyde from poorly installed insulation.

The amount of formaldehyde released by UFFI was highest when first installed and decreased over time.

As a result, UFFI installed before 1980 would have little effect on indoor formaldehyde levels today.

If UFFI gets wet, however, it could begin to break down and may release more formaldehyde. Wet or deteriorating UFFI should be removed by a specialist and the source of the moisture problem should be repaired. Some provinces require homeowners to declare if they have UFFI installed, and this issue is generally raised during the re-sale of older homes.

For more information on UFFI please see Health Canada's It's Your Health factsheet on Formaldehyde or the Canada Mortgage and Housing Corporation (CMHC) - Health Canada, "Formaldehyde in Indoor Air", Health Canada . Sante Canada, retrieved 29 March 2015, original source: http://www.hc-sc.gc.ca/ewh-semt/pubs/air/formaldehyde/fact-info-eng.php

See also

UFFI CLASS ACTION LAWSUIT, CANADA

Research on UFFI Health Effects

 

Our photo shows the dark dusty skin on UFFI insulation where it oozed from a wall cavity opening into a crawl space in the attic over a building garage.

• Also see the links to UFFI ARTICLES & RESEARCH at the end of this page
• Azuma, K., I. Uchiyama, and K. Ikeda. "The risk management for indoor air pollution caused by formaldehyde in housing: The historical perspectives on early warnings and actions." Facilities 24, no. 11-12 (2006): 420-429.
  
  Abstract excerpts:
  Purpose ‐ In order to clarify the determining features of approaches adopted in policies for regulating indoor air pollution, this paper analyzes case studies of the approaches taken, in four countries, to risk management of indoor air pollution caused by formaldehyde in housing.
  
  Design/methodology/approach ‐ We pursued case studies to provide historical perspectives on early warnings and actions taken in relation to suspected health hazards from exposure to formaldehyde, in Germany, the USA, Canada and Japan.
  
  Many investigations of indoor air pollution caused by formaldehyde in housing have been conducted, and regulations established, in these countries. We reviewed the vast quantity of literature and documents relating to governmental and/or industrial actions and of research on indoor air quality produced in the past 40 years, and compared the approaches adopted.
  
  Findings ‐ The study identified the differing character of the approaches adopted in policies for the regulation of indoor air pollution, in order to clarify the range of actions that may be taken in response to reported risk from indoor air pollutants and describe possible risk management models for indoor air pollution.
  
  Practical implications ‐ Understanding of the nature of approaches already adopted will help to preserve good indoor air quality and minimize health hazards due to indoor air pollution.
  
  Originality/value ‐ This paper identifies a range of actions that have been taken in response to suspected risk from indoor air pollutants, through the analysis of its case studies.
• Bissett, John. "Fungi associated with urea-formaldehyde foam insulation in Canada." Mycopathologia 99, no. 1 (1987): 47-56.
  Abstract:
  
  Sixty-eight fungal taxa were identified from samples of urea-formaldehyde foam insulation taken from Canadian residences. Mesophilic taxa were predominant, with Penicillium spp., Trichoderma harzianum and Paecilomyces variotii observed most frequently.
  
  Extensive or conspicuous growth also was seen for Hormoconis resinae, Stachybotrys chartarum and Trichoderma viride in some samples.
  
  The potential for these fungi to have contributed to the adverse health effects reported in some homes containing UF-foam insulation is discussed.
• Day, J. H., R. E. Lees, R. H. Clark, and P. L. Pattee. "Respiratory response to formaldehyde and off-gas of urea formaldehyde foam insulation." Canadian Medical Association Journal 131, no. 9 (1984): 1061.
• Elinson, Lynn. "Health policy and epidemiology: the scientific evidence for a ban of urea-formaldehyde foam insulation." Journal of public health policy 5, no. 4 (1984): 513-537.
• Frigas E, Filley WV, Reed CE: ASTHMA INDUCED BY DUST FROM UREA-FORMALDEHYDE FOAM INSULATING MATERIAL [PDF] Chest 1981; 79: 706-707
  Abstract:
  
  A patient developed severe asthma following insulation of her house with urea-formaldehyde foam.
  
  Bronchial challenge with the buoyant dust of the foam caused an asthmatic attack; inhalation of formaldehyde, 3 ppm, did not.
• Frigas, E., W. V. Filley, and C. E. Reed. "UFFI Dust: Nonspecific Irritant Only?." Chest 82, no. 4 (1982): 511-512. [Letter] included in the PDF below
• Gesser, H. D. "The reduction of indoor formaldehyde gas and that emanating from urea formaldehyde foam insulation (UFFI)." Environment international 10, no. 4 (1984): 305-307.
  Abstract:
  
  It is shown that the addition of ammonia to urea formaldehyde foam insulation (UFFI) can reduce the release of formaldehyde from the foam. Other amines are also effective, indicating that the residual acid may be an important cause of the UFFI decomposition.
  
  Measurements of pH slurries of the foam confirm this. By circulating indoor air through filters treated with polymeric amines, it is possible to reduce the formaldehyde level in homes.
• L'Abbé, Kristan A., and John R. Hoey. "Review of the health effects of urea-formaldehyde foam insulation." Environmental research 35, no. 1 (1984): 246-263.
  
  Introduction Excerpt:
  
  Much controversy exists over the health effects of urea-formaldehyde foam insulation (UFFI),* and in many instances, the information reaching the public has very little scientific basis. The extent to which symptoms felt in the home can be attributed to the presence of UFFI is a major point of contention.
  
  Several investigators have suggested that formaldehyde emanation from UFFI and, consequently, formaldehyde concentrations in the air of dwellings may be the main cause of the alleged health problems.
  
  Some studies indicate, however, that formaldehyde may not be responsible, and that other presently unknown ingredients or some undefined interactions of chemicals in the home may be the cause of these putative health effects.
  
  A review of the pertinent literature will serve to dispel misinformation and to establish a framework for future research. Epidemiologic studies give the most direct evidence of the potentially detrimental health effects of UFFI, and several studies have now been conducted.
  
  Indirect evidence can be provided by epidemiologic studies on occupational exposure to urea-formaldehyde and formaldehyde-containing manufacturing processes.
  
  Laboratory studies on the toxicity, mutagenicity, and potential carcinogenicity of urea-formaldehyde and related products provide further essential indirect evidence for human health effects. Although epidemiologic investigations are more likely than laboratory studies ...
• Lees, R. E. M. "Formaldehyde in insulation: villain or innocent bystander?." Canadian Family Physician 29 (1983): 1127.
• Newhouse, Michael T. UFFI DUST: NONSPECIFIC IRRITANT ONLY? [PDF] Chest 82, no. 4 (1982): 511. [Letter]
• Norman, G. R., and M. T. Newhouse. HEALTH EFFECTS OF UREA FORMALDEHYDE FOAM INSULATION: EVIDENCE OF CAUSATION [PDF] CMAJ: Canadian Medical Association Journal 134, no. 7 (1986): 733.
  
  Abstract:
  Studies of health effects of urea formaldehyde foam insulation (UFFI) were critically reviewed by means of accepted rules for evidence of causation. Three categories of health effects were examined: reported symptoms, primarily of the upper respiratory tract, lower respiratory tract disease and cancer.
  
  Most of the studies purporting to demonstrate health effects of UFFI failed to meet minimal methodologic criteria for evidence of causation. Evidence from the adequate studies provides little support for the hypothesis of a causative role of UFFI in health problems.
  
  Excerpt: Although there are biologic reasons to believe that exposure to formaldehyde might exacerbate asthma, only one case of asthma from exposure to UFFI has been reported in the literature, by Frigas and colleagues.27
  
  This case was paradoxical in that the patient showed a response to UFFI dust but not to formaldehyde. The report has been challenged on methodologic grounds.28 Frigas and colleagues"9 also reported a subsequent study in 20 subjects who presented with asthma suspected of being related to UFFI.
  
  In direct challenge testing none of the subjects showed a response consistent with UFFI- or formaldehyde-induced asthma.

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

What is this orange crumbly foam like stuff in my attic? Asbestos?

Hi Any idea what type of insulation this is? Asbestos? - On 2020-10-17 by Dominic C -

Reply by (mod) -

I can't quite say with certainty, Dominic because the photo is a bit blurry.

Is that a crumbly foam material? Installed perhaps in the 1970s?

If so it's perhaps UFFI? Urea Formaldehyde Foam Insulation.

See those details in the article above on this page.

This Q&A were posted originally at INSULATION IDENTIFICATION GUIDE

Buying a building with UFFI - must we remove it?

Considering purchase of a building with UFFI. Put between exterior and interior brick. Done in 1970s, no formaldehyde in air. Must we still remove it? - On 2015-06-16 by Carolyn -

This Q&A were posted originally at FOAM SPRAY INSULATION TYPES

Reply by (mod) - No, not unless there are significant voids - no health reason to remove UFFI from an old building?

In my opinion there would be no justification whatsoever for removing UFFI from a 1970's installation.

Even if there was an original mis-mix of the insulating foam and formaldehyde outgassing, that outgassing would have finished decades ago. If there were a formaldehyde problem in your building I'd suspect it of coming from newer materials.

There may be a more subtle issue. Homes I disassembled where UFFI had been pumped into walls often had incomplete insulation and air leakage around the sides and top of each wall cavity stud bay because the UFFI shrank.

See details at UREA FORMALDEHYDE FOAM INSULATION, UFFI - topic home

Do I have to worry about UFFI that we bagged and threw out?

We took down the wallboard in our kitchen for a remodel project. We found Kimsul, blown in cellulose insulation and what I think is UFFI. We just bagged it all and put it in the dumpster. We work respirator face mask labeled for mold and lead. Do I have more to worrie about - On 2013-01-26 7 by wadewoman - D

Reply by (mod) - no but clean up dust

The only additional suggestion I'd have would be to clean up any remaining dust from your demolition. I use damp wiping and HEPA vacuuming.

Can UFFI lead to structural wood rot?

Hi!

Is it true that UFFI could potentially lead to the rottening of the wood structure of a house because there was no air space left between the bricks and the house (the air space was filled with UFFI)?

Thanks! - On 2012-09-23 by Sean -

Reply by (mod) - no, not directly. Leaks into any building walls are, however, a rot and insect damage concern.

Sean,

Your suppostion is reasonable but in my OPINION incomplete, and the hidden damage that occurs if we have leaks into an un-vented foam- filled building cavity is not peculiar to UFFI but rather to any un-vented, foamed cavity, especially if the foam is an open-celled foam that is more able to absorb and hold water.

The root problem is a leak into a cavity on any building. And the ensuing damage isn't caused by the foam. Even a conventionally-framed wood stud wall or "hot roof" insulated with fiberglass will suffer rot and risk insect attack aggravated by
trapped moisture.

While there are widely-liked experts who tout the hot roof design, practical field experience shows that roof leaks do happen over the life of a building, due to construction errors or events in nature (a falling tree branch, a hurricane that blows off roofing, etc), or due to aging and wear and tear.

And leaks into an airtight cavity tend to go unnoticed until the damage is severe.

Is crumbling and dusting UFFI a health problem ?

Is crumbling and dusting UFFI a health problem or cause of breathing issues? - On 2011-12-22 by JNZ@yahoo.com - I

Reply by (mod) - health worries about UFFI centered on formaldehyde outgassing

JNZ

The original health worries about UFFI centered on formaldehyde outgassing - itself a controversy. Indeed having inspected old UFFI installations decades later, in addition to the shrinkage that we report above, we found that the material in-situ is quite fragile and is easily crushed or crumbled to powder by hand.

It would be very unlikely that one could detect airborne particles of UFFI in the interior of a building whose enclosed wall or ceiling cavities contain this insulating material. The dust issue should arise if there is demolition or remodeling work that has to disturb the material, in which case good dust control measures would be appropriate since in my OPINION any fine particulates are a potential respiratory irritant.

How can the Health Canada IAQ Test for formaldehyde GAS in the Building Envelope?

How can the Health Canada IAQ Test for formaldehyde GAS in the Building Envelope in any way be a fair test procedure when their are 267 other formaldehyde sources of Formaldehyde being tested inside the indoor contaminated test area?

2nd How can this test result of a GAS in one area possibly relate in any way to a Quasi Pre-polymer Solid Cellular Plastic (UFFI) in a completely different Outside Area, separated by a Canadian Building Code Mandatory Vapor Barrier outside the indoor air test area.

3rd Isn't this just Junk Corrupt Canadian Government Science and Fear Mongering solely to extort industry kick backs, verifyable by UFFI Industry experts clearly advised that testing inside air only provides test results for the ubiquitous indoor formaldehyde gas from other indoor products?

4th How can Health Canada possibly justify the stigmatization of homes all across Canada for no just Scientific Health Safety Reason. Retrofoam Insulation a health safety hazard as claimed by Health Canada is seriously flawed It's impossible

Well what do you have to say about my comments? - On 2011-12-01 by ajefford@yahoo.com -

Reply by (mod) - crumbling and dusting UFFI and no current offgassing issue

Ajefford, we agree with the question you raise, that there can be multiple sources of formaldehyde outgassing in a building.

And breathing any very small dust particles can be a respiratory hazard;

There is no data supporting a claim that homes insulated with UFFI in the 1970s have a formaldehyde off-gassing problem that would be traced to that insulation today.

Depending on how and where a test is conducted, however, an narrow down or even eliminate that confusion.

In our OPINION the bottom line is that even when improperly mixed and installed so that formaldehyde outgassing occurred in UFFI insulation jobs (typically during the 1970's in North America), the open celled foam outgassed completely over several years at most. It is unlikely that we can detect formaldehyde outgassing today from 40 year old foam.

 

Thank you to our readers for their generous comments

Nice thanks for very good info. God bless you - On 2012-12-11 by Arif

Identify UFFI or Urea Formaldehyde Foam Insulation in buildings

This topic has moved to a separate article found

at UFFI, HOW TO IDENTIFY in BUILDINGS

How to Find & Identify UFFI Insulation in an Older Home by Visual Indoor Inspections: Insulation Retrofit Projects

At UFFI, HOW TO SPOT A RETROFIT INSULATION JOB we give specific inspection methods useful in building interiors and exteriors that will help spot the types of insulation that may have been added to a building over its life.

How to Spot UFFI Building Insulation in an Older Home by Visual Outdoor Inspections: Insulation Retrofit Through Siding

This discussion has been moved to UFFI, EXTERIOR INSTALLATION SIGNS

Urea Formaldehyde Foam Insulation UFFI Shrinkage and Air Leaks

Please see UFFI SHRINKAGE, THERMAL BYPASS LEAKS

Calculating the Heat Loss Due to UFFI Insulation Shrinkage

See UFFI SHRINKAGE LEAK IMPACT CALCULATION

Should UFFI Insulation Affect the Sale Price of a Home?

We have moved this discussion to UFFI INSULATION IMPACT ON HOME SALE PRICE

UFFI Urea Formaldehyde Insulation Class Action Lawsuit

This discussion is now found at UFFI CLASS ACTION LAWSUIT, CANADA

...

Continue reading at UFFI, HOW TO IDENTIFY in BUILDINGS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see UREA FORMALDEHYDE FOAM INSULATION, UFFI FAQs - questions and answers posted originally at this page

Or see these

Recommended Articles

• FORMALDEHYDE GAS HAZARD REDUCTION - measures to reduce indoor formaldehyde levels
• INSULATION IDENTIFICATION GUIDE - home
• INSULATION LOCATION - WHERE TO PUT IT - home
• UREA FORMALDEHYDE FOAM INSULATION, UFFI
  • UFFI in BUILDINGS, SUMMARY
  • SHOULD YOU AVOID BUYING a UFFI-INSULATED HOME?
  • UFFI, HOW TO IDENTIFY in BUILDINGS
  • UFFI, HOW TO SPOT A RETROFIT INSULATION JOB
  • UFFI, EXTERIOR INSTALLATION SIGNS
  • UFFI REMOVAL PARTICLE SIZE HAZARDS
  • UFFI SHRINKAGE, THERMAL BYPASS LEAKS
  • UFFI SHRINKAGE LEAK IMPACT CALCULATION
  • UFFI INSULATION IMPACT ON HOME SALE PRICE
  • UFFI CLASS ACTION LAWSUIT, CANADA
• URETHANE FOAM Deterioration, Outgassing

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UREA FORMALDEHYDE FOAM INSULATION, UFFI - topic home, at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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INDEX to RELATED ARTICLES: ARTICLE INDEX to BUILDING INSULATION

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Citations & References

In addition to any citations in the article above, a full list is available on request.

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