You can claim standard deduction as well as interest Deduction for commercial property upto net annual value that is gross rent minus municipality tax but if there's is loss then no set off with any income head as per new rule and you can not take principal Deduction
You can claim it by showing it as an Expense in the debit side of Profit & Loss A/c under the head PROFITS & GAINS FROM BUSINESS OR PROFESSION ( PGBP ).