Getting contact information
It is already short and to the point. One minor formatting change; I would make your class properties upper camel case, which is typical for C#. I also dropped the abbreviations.

public class Address {     
   public string HouseNumber { get; set; }     
   public string Street { get; set; }     
   public string Zip { get; set; }
}

public class Contact {     
   public string Email { get; set; }     
   public string PhoneNumber { get; set; }     
   public Address Address { get; set; } 
}