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UFFI – Putting the record straight

WHAT IS UFFI? (Pronounced You-Fee)

Injected foam insulation - UFFI was injected in a similar fashionThe full name of UFFI is “Urea-formaldehyde foam insulation” and it was developed in Europe in the 1950s as an improved means of insulating difficult-to-reach cavities in house walls.

It is made from a mixture of urea-formaldehyde resin, a foaming agent and compressed air.  When the mixture is injected into the wall, urea and formaldehyde unite and cure into an insulating foam plastic. During the 1970s, when concerns about energy efficiency led to efforts to improve home insulation in Canada, UFFI became an important insulation product for existing houses. Most installations occurred between 1977 and 1980 when it was banned in Canada.

Why was it banned?

In the insulating process, a slight excess of formaldehyde was often added to ensure complete curing with the urea to produce the urea-formaldehyde foam. The excess formaldehyde was given off during the curing, almost entirely within a day or two of injection.  Properly installed, UFFI might not have resulted in any problem.

Unfortunately, however, UFFI was sometimes improperly installed or used in locations where it should not have been.

The Canadian authorities received many complaints, particularly, from people living in small, well-sealed homes, became concerned about possible health implications.  Instead of regulating the way builders installed the foam, and enforcing checks to ensure they did things properly, they banned further use of UFFI in 1980.

Should you be concerned about UFFI today?

Between 1980 and 1993 a UFFI declaration was required for all homes that were sold that were known to have UFFI installed.  Since 1993, after changes to the National Housing Act, a UFFI declaration has not been required for mortgage insurance.  The SPIS may still require you to declare if UFFI is still installed in the property.  ( Before you sign an SPIS read this link ) and depending on your location you may need to disclose by Law that UFFI is installed.

All this said tests show that UFFI is not a source of over-exposure to formaldehyde after the initial curing and release of excess gas. The likelihood of UFFI, last installed in 1980, causing excess indoor formaldehyde today is very remote. Houses with UFFI show no higher formaldehyde levels than those without it.

Are there any other problems with UFFI?

UFFI is highly absorbent.  Given 95% humidity, UFFI will absorb anything from 25% to 100% of that humidity.  Given dryer conditions, UFFI can take up to 14 days to return to its dry state.  On a hot, humid day with Relative Humidity at 90-95%, any exposed UFFI insulation is absorbing that moisture.  It will release it back into the cavity of your home over the next 14 days.  (Reference)  Moisture and homes don’t mix.

Additionally, as the UFFI breaks down, it’s efficiency as an insulator reduces too.  If wet UFFI is exposed to the right conditions it may start to off-gas again or create formic acid which gives of a pungent smell in its own right.

Does it have to be removed?

No, UFFI does not have to be removed, and insurance companies cannot (legally) refuse to insure a house with UFFI, some still do however using other excuses.  If you do want to remove UFFI, however, it is VERY expensive.   Removal has to be completed by a qualified and licensed person and only AFTER receiving a permit.

Is formaldehyde bad for you?

In a word Yes.  But it’s not considered dangerous in small quantities.  “How much is small”? is a matter for debate.

The Government and most scientific studies say that prolonged exposure, to anything higher than one-tenth of one part per million, was bad for you.  UFFI has never been shown to give off more than that in the curing process, but in Canada and the U.S. it was banned.  (Although that decision was reversed in the U.S.) and it is still used for Cavity wall installation in Europe, which has much higher standards of environmental control than us.

Interestingly enough Formaldehyde is also given off by new carpets, plywood, other glued materials and Kerosene.  In fact houses with new carpets approached the “bad area” of 0.5 ppm but no one was has outlawed carpets, MDF cabinets and furniture or Kerosene heaters.


UFFI is one of the most thoroughly investigated, and most innocuous building products we have used. After the longest and most expensive civil case ever held in Canada (eight years) was concluded in the Quebec Superior Court, not only was no basis for a settlement found, but the plaintiffs were obliged to pay for most of the costs.

If your home or prospective home has UFFI, it has been properly installed, is not exposed to moisture, and you don’t need to rip out any walls to expose it, there is no proven evidence why it should pose any greater threat to your health than many other items that you still purchase and place in your home today.

What can be drawn from all this is that UFFI has not been shown to be a health hazard.

That said, with court cases across the country ending in fines for Vendors and Realtors ranging from $25,000 to $250,000 and in some cases bankrupting the homeowner it’s best to get the property inspected to see if it has, or it hasn’t got UFFI rather than guess and be wrong, and don’t sign an SPIS until you’ve done so and spoken to your lawyer.


On February 3, 2009, Health Canada announced that RetroFoam contains urea formaldehyde (“UFFI”) a substance which is banned in Canada under the Hazardous Products Act.   A subsequent class action lawsuit was launched.  This was a different type of Lawsuit because it’s not just against a manufacturer or installer, but also against the Government of Canada.

The government of Canada is named in the suit because many of the homes were insulated under the federal governments ecoENERGY retrofit program. The claim is that because the insulation work qualified for the energy efficiency grants — that is, a homeowner had more insulation added and that increased the house’s R-value — that implied that the government endorsed the products used.

Health Canada published a report on their website. It was archived in June of this year (2013).  You can read the original report here

It is interesting to note that the Lawsuit doesn’t claim the foam to be a health hazard, merely that homes insulated with it will be stigmatised, and therefore attract lower selling prices.