Can I cover over my existing roof?

Installing a roof over the top of an existing roof is generally acceptable under these guidelines: 1) A building cannot have more than two roofs; 2) No wet insulation can be left in place; 3) The roof structure must be able to handle the additional roof load; 4) The new roof must be attached to the roof deck to meet wind loads (it is not generally acceptable to adhere the new roof to the old roof).