It sounds like you are working backwards. The land is only incidental to the house. Did you finish building the house? You have to total your building costs to arrive at the amount of the house. This only matters if it is going to be a rental property.
If this is to be your own home, so long as the home becomes your main home or second home on the day it's ready for occupancy, you can deduct all the interest you paid on the construction loan within 24 months before the home was complete.
