Urea-formaldehyde foam insulation — a foam pumped into wall cavities in the 1970s to improve efficiency. It was banned in Canada in 1980 after concerns about formaldehyde off-gassing.
Removal is costly and rarely required; the main impact is disclosure and resaleAddress soonInsulation
Why it matters
In homes insulated decades ago, the formaldehyde off-gassing has largely dissipated, and research found cured UFFI is not a significant ongoing health hazard. The practical issues today are disclosure and resale: UFFI often must be disclosed, it can make some buyers and lenders wary, and — because the foam can hold moisture in a wall cavity — it can contribute to hidden rot where there is a water problem.
How to spot it
You usually can't see it, because it's inside the walls. Clues include a UFFI test or disclosure in the paperwork, off-white foam visible at removed outlets or along the attic wall-top, and a home insulated in the late 1970s. A certified test (air sampling or a core sample) confirms it.
What it costs
Removal is disruptive and expensive and is rarely required for safety. The real cost is usually the effect on resale and financing, plus any moisture damage the foam has masked.
What to do
Ask whether the home has UFFI and for any test results. If it's present, don't panic about health for old, cured foam — focus on disclosure, moisture, and how lenders and buyers in your market treat it. Get a professional test if it's unclear, and have an inspector check for related moisture.
Education and triage, not a home inspection. Casaroo prompts the UFFI question for late-1970s homes — a certified tester confirms it and an inspector checks for moisture. We flag; we don't test.
Common questions
What is UFFI (urea-formaldehyde foam insulation)?
Urea-formaldehyde foam insulation — a foam pumped into wall cavities in the 1970s to improve efficiency. It was banned in Canada in 1980 after concerns about formaldehyde off-gassing.
Why does it matter for home buyers?
In homes insulated decades ago, the formaldehyde off-gassing has largely dissipated, and research found cured UFFI is not a significant ongoing health hazard. The practical issues today are disclosure and resale: UFFI often must be disclosed, it can make some buyers and lenders wary, and — because the foam can hold moisture in a wall cavity — it can contribute to hidden rot where there is a water problem.
How can I spot it?
You usually can't see it, because it's inside the walls. Clues include a UFFI test or disclosure in the paperwork, off-white foam visible at removed outlets or along the attic wall-top, and a home insulated in the late 1970s. A certified test (air sampling or a core sample) confirms it.
How much does it cost to fix?
Removal is disruptive and expensive and is rarely required for safety. The real cost is usually the effect on resale and financing, plus any moisture damage the foam has masked.
Confirm current disclosure rules in your province.
Last reviewed 2026-07-02.
This guide is general education, not a home inspection and not advice for your specific property — always
consult the appropriate licensed professional, and get a licensed home inspection before you remove conditions
or buy. Cost ranges are 2026 estimates that vary by region, size, and access; confirm specifics with a
qualified professional.