It seems like your original intent when you purchased the property was to keep the structures. That usually means you can deduct the cost of the building.
https://www.law.cornell.edu/cfr/text/26/1.165-3However, if it were to be determined your intent at the time of purchase were to demolish the building, unless you made the election to put the property in a General Asset Account (that is unusual, box 18 of your 2015 Form 4562 would be checked), demolition puts the basis/loss into the basis of the land. You don't get anything until the land is sold.
https://www.law.cornell.edu/uscode/text/26/280B
