UFFI (Urea Formaldehyde Foam Insulation) recognition & identification in buildings.
This article explains simple ways to distinguish UFFI from other types of foam insulation found in buildings.
We also describe visual clues that indicate that an insulation retrofit job has been done at a building from outside or inside.
We include identification photographs and a description of a very simple field test that can immediately distinguish between 1970's vintage sprayed or pumped UFFI insulation and more contemporary icynene or polyurethane spray foam insulation jobs.
This article series on UFFI insulation 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.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
Our photo shows the dark dusty skin on UFFI insulation (Urea Formaldehyde Foam Insulation) where it oozed from a wall cavity opening into a crawl space in the attic over a building garage.
If you are having trouble determining what type of foam insulation product has been installed in a building,
see FOAM SPRAY INSULATION TYPES for more detail on the identification of these products in the field.
There you will see more examples of the foam insulation press and crush test that our photos illustrate just below.
If the insulation is UFFI, it easily crushes to a fine powder - (below).
Below 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.
Look at interior or exterior building walls for evidence of openings that were cut or drilled to blow-in building insulation.
Since the same type of round openings are used for blowing in cellulose or at least two different types of foam building insulation, if you see these marks or round hole cuts you will need to investigate further to identify the specific type of insulation that was installed.
Our photo above shows interior drill holes in an attic stairwell where insulation was pumped into the building wall cavities. Why so many holes? The first cuts probably hit wood framing.
Photos of typical holes found in a building exterior where insulation was blown or pumped into the wall cavities are provided in detail below
at
How to Spot UFFI Building Insulation in an Older Home by Visual OUTDOOR INSPECTION
Look in basements and crawl spaces for evidence of UFFI (crumbly) foam exuding out into the basement or crawl space at the bottom of wall cavities.
Often there were gaps that permitted this foam escape - usually it was just left in place.
Where balloon framing techniques were used, depending on the adequacy of fire blocking in wall cavities, foam injected into the walls may have passed between floor levels and easily into an attic (as shown in our PHOTO above) or into the basement or crawl space as shown below in the left hand photo.
Look in un-finished areas such as attics and closets
where plaster and lath are left incomplete or where drywall has been omitted during a building retrofit.
Our photos below show UFFI insulation pushing on a poly plastic vapor barrier. Someone has cut the poly in the left photo, perhaps to sample the material - a step that was unnecessary if the inspector simply looked down at his or her feet (photo below-right).
You may also be able to see UFFI or other types of foam insulation oozing out from large openings at the sill plate between floors (photo below-left) or UFFI foam may have oozed out of even small wall openings as we show in the right hand photo of an un-finished plaster lath wall (below right).
Look for small amounts of soft crumbly foam insulation at tiny openings
in wall cavities such as at knot-holes or gaps between siding boards, as we show on our photo (left).
You may need to probe this material to evaluate its density and fragility. If the material easily crumbles to a powder, it is probably Urea Formaldehyde Foam Insulation or UFFI Foam.
Look for scalloped drywall on the inside surface of building exterior walls:
often the UFFI foam insulation was sprayed with more water content than specified; because the insulating material could be quite wet when first installed, we found that in some old homes which had been renovated by replacing original plaster with drywall, the drywall became wet, bonded to the UFFI, and then actually became sunken or concave along the building exterior walls as the UFFI insulation cured.
We pose that the drywall had become soft while wet, that it bonded to the UFFI in the wall cavity, and that as the UFFI insulation dried and cured it also shrank, pulling the damp drywall sections inwards.
We first spotted this phenomenon in an 1890 home in Wappingers Falls, NY when the home was insulated with UFFI spray in the 1970's.
Looking along the top edge of the baseboard trim at the bottom of the wall we saw that the drywall was in contact with the trim only at the location of the wall studs, and that between each pair of studs the drywall was concave.
As our pumped-in UFFI insulation retrofit job photos show, plugs may be visible in siding boards, but we warn that they also may have been covered by replacement boards or by a new layer of exterior siding.
Also this plug and pump method for blowing insulation into building walls was used for more types of insulation than just UFFI.
...
Below you will find questions and answers previously posted on this page at its page bottom reader comment box.
I’ve searched all over and posted on many forums. Nobody can seem to identifying this insulation. It looks hard but it’s soft like sand/flour when touched. It crumbles with easy.
I’ve heard it may be DE, perlite, walite , UFFi insulation and more.
Older home but it was updated at some point.
I am a NYS asbestos inspector and the owner wanted it tested for asbestos. Do you have any idea what type Of insulation this is? - Anonymous by private email 2023-09-05:
Thank you to Adam Clark, a New York home inspector, for these photos and the UFFI Discussion - Ed.
Reply by (mod) - looks like UFFI though whiter than usual; UFFI crumbles-to-powder - try that
Bottom line: What you were describing sounds like and looks like UFFI. It would be very helpful to know more about the building such as the building's actual age and when you think the insulation was installed.
Can you post a photo of the crumbled material? While other, newer foam insulating products vary from hard to soft, I've not found versions other than UFFI that crumble to a grainy powder simply with the use of a hand or fingers.
It does not look to me like
PERLITE INSULATIONI am not familiar with "walite" insulation, though perhaps you meant "WALLTITE" a modern closed cell polyurethane spray foam (SPF) insulating brand produced by BASF. I have not found a polhurethane spray foam insulation that was "crumbly."
Please elaborate or expand "DE" insulation - I'm not sure what you're referring to.
Did you search our website and read our descriptive information
about UREA FORMALDEHYDE FOAM INSULATION, UFFI ?
I also recommend scanning
OPINION: I can't imagine any reason to test that spray foam insulation for asbestos.
I don't think we'll find a research source that cites deliberate combination of asbestos material with foam insulation. If you have come across that's your reference I sure would like to know about it.
However I have found older homes where spray foam as well as other products were applied over older asbestos insulation such as around pipes - as an insulating encapsulant.
Bottom line: UFFI - Urea Formaldehyde Foam Insulation - not an asbestos product.
I look forward to hearing more from you on this and to seeing photos of the crumbled insulation. - Daniel
Reader follow-up: This is UFFI Insulation
I've come to the Conclusion it is UFFI insulation. Looks like it broke down over the years. Thank you for always responding to my emails . I love your website.
Moderator reply
I agree with your conclusion - after we started discussing this I looked back though my photos and notes including some of the photos above on this page and confirnmed that indeed some of the UFFI I've found in buildings was dead white while other was quite yellow - sometimes side by side.
Reader follow-up: This is UFFI Insulation - test confirmed no asbestos
Up close the insulation has a light gray tint to it that you can't see in the picture. The text resembles wet sand and crumbles in your hand when you apply limited pressure. As it crumbles it feels like sand/flower.
The flash on the camera makes it look a little more white than it is. The contractor wanted it tested for asbestos so we did. Results were 100% non fibrous.
...
Continue reading at UFFI SHRINKAGE, THERMAL BYPASS LEAKS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
Or see these
UFFI, HOW TO IDENTIFY in BUILDINGS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.
Or see this
Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia
Questions & answers or comments about how to recognize UFFI Urea Formaldehyde Insulation in buildings.
Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Search the InspectApedia website
Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.
Only one image can be added per comment but you can post as many comments, and therefore images, as you like.
You will not receive a notification when a response to your question has been posted.
Please bookmark this page to make it easy for you to check back for our response.
Our Comment Box is provided by Countable Web Productions countable.ca
In addition to any citations in the article above, a full list is available on request.