Urea formaldehyde insulation & removal

Urea formaldehyde is an excellent synthetic insulation. It was a popular choice for insulation in the seventies. In 1977 the Congressional Research Service estimates that there may have been over 200,000 installations. Although effective, it was banned by the United States Consumer Product Safety Commission in the early eighties for use in schools and residences. The Environmental Protection Service (EPA) recognises urea formaldehyde insulation as a source of formaldehyde emissions which, in high doses, has been shown to cause cancer in animals.


Urea formaldehyde insulation was manufactured in the fifties but became popular in the seventies as energy prices began to rise. It is foam with the consistency of shaving cream. It is a retrofit upgrade and easily injected into an existing wall using hoses. Once injected, the Urea formaldehyde insulation hardens within a few minutes and cures in less than one week. Formaldehyde gas is emitted during the curing process and for some time thereafter.

Health Effects

Formaldehyde off-gassing causes negative health effects in some individuals. According to the EPA, it can cause "burning sensations in the eyes and throat, nausea, and difficulty in breathing in some humans exposed at elevated levels (above 0.1 parts per million)." People with asthma are known to be especially sensitive to formaldehyde and others develop an allergy when exposed to high concentrations.


Look for urea formaldehyde insulation in buildings built before the seventies. Basements, attics, crawl spaces and unfinished closets are easy places to discover it. A good clue that you may have urea formaldehyde insulation is round holes in the interior walls or plug holes in the exterior walls of the structure. These signs may also indicate that there is latex foam spray insulation or icynene foam spray insulation.

Upon a visual inspection, although solid, its hardened shape looks like an oozing liquid. With age, it can turn to shades of butterscotch but freshly injected, it is a light yellow. Unlike the other types of foam insulation, the urea formaldehyde insulation undergoes significant shrinkage.The skin has a dull, matt finish, not shiny. The texture should be dry and crumble easily. Use a pen as a probe to test the insulation.


Removal of urea formaldehyde insulation is expensive. First the offending walls must be opened to remove the foam. Building Inspector Mark Visser says the next step is "neutralising the wall cavity with a sodium bisulphite solution." Then replace the original drywall or plaster. This work should be done by a certified Restoration Environmental Contractor. Official protocols should be followed for both removal and disposal and should only be carried out by qualified personnel.

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