From what I am reading, you would not be able to claim the work on the barn. Some buildings are allowed, but they have to be built, such as a deck, garden shed, or garage.  The property included in the "principle residence" is only 1/2 a hectare or 1.24 acres. You can contact CRA for further clarification at [phone number removed]. You may get answered faster if you call during the afternoon.

You can also contact Saskatchewan  government services at [phone number removed] to clarify.