I have blogged in the past about Urea-formaldehyde insulation, and I still frequently find it on inspections. Many people still have vague recollections of its being a problem in the past. And of course the Canadian government still thinks it is a big issue–while the EPA is relatively mute on the subject (although they do have a lot to say about Formaldehyde in pressed wood products). Buyers always want to know what its presence in the home will mean to them going forward with the transaction.
This type of insulation was the “super insulation” of its day and it held promise of being a significant player in saving energy during the Oil Crisis of the mid 1970’s.
There were some early reports of people having respiratory issues after having their homes insulated with the stuff and the media had a field day with it. Like so many things the media gets a hold of, Urea-Formaldehyde was crushed as a viable means of insulating homes. And of course the fact that Formaldehyde is a known carcinogen in animals fanned the flames. The respiratory fears were later found to be unfounded (except in extreme cases) but by then it was too late and its use was mostly abandoned as newer spray foams were developed that did not contain formaldehyde.
There were plenty of other factors to account for the increased incidences of respiratory issues. One factor was making homes tighter and not making provisions to have adequate air changes in the home. It wasn’t “rocket science” but it did encourage a whole new field of study that has become known as “building science.” Most experts today assert that most elevated Formaldehyde levels in homes with Urea-formaldehyde insulation actually is the result of out-gassing of furniture, carpet padding and other formaldehyde emitting sources within the home.
But that was then–this is now. So what about finding the stuff in homes today?
The biggest problem with its presence today is that it makes lousy insulation. In this case the media killed the product for the wrong reasons–reasons only discovered when the first remediations were undertaken. The stuff shrinks like crazy–anywhere from 10% to 15% in all directions–leaving a block of insulation in the wall cavity completely surrounded by air that can form convective loops. Convective loops are what moves air–supporting and encouraging the transfer of heat-to-cold through the wall. This is not a good idea if you want the insulation to do the best job.
As a builder I have found Urea-formaldehyde insulation when taking apart walls. It always dramatically demonstrated how much it shrinks. Occasionally as an inspector I find small examples. The following pictures were taken in a home where someone had taken off the wall finishes exposing the insulation–leaving it for me to get some good pictures.
When found, remediation was and is difficult. Some jurisdictions (Canada) require special protocols for removal. Mechanical means of breaking the stuff up in the cavity and then vacuuming it out of the space were attempted in the early days of trying to get rid of it–but there were risks with this approach because wiring and other elements in the wall could be damaged–not to mention that the stuff would not be truly cleaned from the cavity. Removing drywall is likewise costly but most likely the best method. Attempts to add insulation around the shrunken insulation were usually less than satisfactory.
What should be attempted for any given house would likely vary with the type of house and other plans for remodeling. Since this insulation was mostly installed in older homes that had no insulation, these homes often need extensive remodeling anyway. Removing wall finishes down to the studs provides an opportunity to get rid of the Urea-formaldehyde insulation as well as facilitating re-wiring and re-plumbing of the home that might also be needed.
Climate would also be a factor, and depending on the area’s heating and cooling needs, doing nothing might be an option as well.
For more information on Urea-Formaldehyde insulation please see the information on the InspectAPedia Website.
Charles Buell, Seattle Home Inspector
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