What is a Building Permit? A Building Permit is a licence which grants legal permission to undertake the construction, alteration, repair or change of use of a building or structure, on private property. Requirements for Permits. Building Permits are typically required for the following: New BuildingsAdditions to existing BuildingsRepair, Renovation and Alteration of Existing BuildingsPrefabricated and Relocated BuildingsBuilding Systems (heating, fire protection, etc.)Various Structures ...