29. Water sprinkler system (for fire control purposes)— new installation(s).
30. Water tank—new installation(s).
31. Windows—new framed windows.
(4) Prior to September 24, 2011, the increase in the monthly stabilization rent for the affected housing accommodations when authorized pursuant to paragraph (1) of the subdivision shall be 1/40 th of the total cost, including installation but excluding finance charges; on or after September 24, 2011, the increase in the monthly stabilization rent for the affected housing accommodations when authorized pursuant to paragraph (1) of this subdivision shall for buildings and complexes containing 35 or fewer housing accommodations be 1/40th of the total cost, including installation but excluding finance charges, and for buildings and complexes containing more than 35 housing accommodations by 1/60th of the total cost, including installation but excluding finance charges; and any increase pursuant to paragraph (2) of this subdivision shall be 1/84 th of the total cost, including installation but excluding finance charges as allocated in accordance with paragraph (12) of this subdivision. For increases pursuant to subparagraphs (2)(iii) and (iv) of this subdivision, in the discretion of the DHCR, an appropriate charge may be imposed in lieu of an amortization charge when an amortization charge is insignificant or inappropriate.
(5) Such increases shall not be collectible during the term of a lease then in effect, unless a specific provision in the tenant's lease authorizes an increase during its term pursuant to an order issued by the DHCR, except that increases pursuant to paragraph (1) of this subdivision may be collected upon installation.