If you are not an individual or HUF assessee then and if total rent payable for the lease period exceeds 180000 then yes, you are required to deduct tax @ 20%.
Deduct TDS @ 10 if whole rent payment for the year is more than 180000/-. here is 20000*12=240000/- second thing is that deduction will be made by individuals and huf only when they're in tax audit Otherwise need not to deduct. ur not tax audit not required to deduct tds.
A person (not being an individual or HUF) is liable to deduct TDS @ 10% u/s 194I on rent payable provided total rent payable in the whole year is more than Rs. 180000/-. Also, If an individual or HUF to whom tax audit is mandatory, is liable to deduct applicable TDS on rent.