The Canada Revenue Agency allows you to sell your primary residence without paying a capital gain when you sell it. There are some exceptions, however, if you lived at your primary residence, but then moved and began to rent it.
For example, if you lived at 155 House Road for five years, and then you rented it for six years. Upon the sale of the house, you would need to calculate the gain from the time you rented it to when you sold it. Therefore, any increase in value for the first five years you lived there would be tax free. Complete Form T2091 to determine the amount to report.
If you had completed form T664 because you sold your primary residence, complete T2091. If you are the authorized person for someone who is deceased, and you sold her primary residence, you will need to complete form T1255.
Other resource links to review (if needed):
CRA T2091(IND): Form T2091(IND)
CRA WS for T2091(IND): WorkSheet