The key points for real estate valuation and the effects of UFFI are:
The insulation was banned by the Canadian government in April of 1981. This was following a 1980 lab study, linking UFFI to cancer. Since then, these results have been disputed, but they have become well entrenched in the public mind.
Approximately 80,000 to 100,000 houses in Canada contained UFFI. A large percentage of these homes were insulated as a direct result of government grants, which were paid to homeowner's who insulated or reinsulated their houses.