What might factor into the cost of your house that would not factor into the cost of rebuilding it

Answer: the cost of the land.

To rebuild you house, you shall need to demolish it and build again from the ground, which will mean that you will have to design it, buy all the materials and construct the new house. But the land remain being the same and, if you do not have a reason to intervene it, it will not be a factor for the cost of rebuilding.