UFFI or cellulose?

I got this picture of insulation by taking a blind snapshot behind the cabinets under the kitchen sink. 1940’s house. This looks like blown-in cellulose type insulation.
Is it reasonable to surmise that this grey material was blown in through these smallish holes in the stucco? Or are they more likely UFFI holes?
I didn’t identify the type of insulation in my report, not enough info.

John Kogel





Not really sure, based upon your picks. However, even if it is UFFI there would be no problem at all now.

UFFI issues, as I understand it, came about as a result of off-gassing of the formaldehyde used to make the insulation fluid.

If it is UFFI, the off-gassing would have ended long ago. Therefore, no problem.

Hope this helps


This is what UFFI looks like…

Tests have shown that UFFI is not a source of over-exposure to formaldehyde after the initial curing and release of excess gas. It was last installed in 1980, and it would certainly not be causing excess indoor formaldehyde today.

Houses with UFFI show no higher formaldehyde levels than those without it. However, if UFFI comes in contact with water or moisture, it could begin to break down. Wet or deteriorating UFFI should be removed by a specialist and the source of the moisture problem should be repaired.

This is the position that CMHC is taking on the subject.


Thanks, guys. I guess my question is: Can the grey fluffy stuff be blown in through those tiny holes?

Yes! did it for years. From the little bit of grey showing in your picture, I’d bet heavily on it being cellulose.

Depends on where you’re located. There is still some fear on the street about this product so some folks will walk when it’s found. If they find it after they buy, could lead to a lawsuit.


Here’s a picture of a hole that is used to install cellulose from the exterior.


The installation hose is basically a tad bigger than a vacuum hose.

Yes, pic #1 looks like cellulose…

The hole in the picture appears 2-2 1/2 inches diam. Cellulose can be installed with nozzles as small as 3/4 inch diameter; these were used when drilling through mortar joint corners in brick veneer to blow the wood structural wall cavities. The holes in the stucco look to be 1’’ diam, a more common size.

Thanks Brian and David. Info like this can really help to reassure a client, and sure sounds more intelligent than “I don’t know”. :stuck_out_tongue:

From Mario’s link, UFFI holes were 1/2" to 3/4" in diam, so generally smaller.

That article is a bit off in the hole sizes used for foam. The article was obviously written by someone in an area with a lot of brick veneer. In my area, when siding removal allowed access to sheathing, the UFFI was installed through 2" holes. When going through brick veneer, concrete block, etc, the smaller holes would be used.



Insulation Handbook By Richard T. Bynum, Daniel L Rubino: states that1/2" to 2" holes were used.

UFFI or cellulose? 7/1/08 12:48 PM For all the bull**** posts and remarks you made on this mb / Raymond Wand & Roy Cooke Sr.

Mario: I thought you always signed **your **name!!

Don’t take my info posts so seriously…the CMHC article was incorrect on hole sizes…not you!!