California Code, Revenue and Taxation Code - RTC § 74.8

(c)(1) Notwithstanding any other law, for purposes of this section, “the construction or addition of a rain water capture system” includes the construction of a rain water capture system incorporated by the owner-builder in the initial construction of a new building that the owner-builder does not intend to occupy or use.

(2) The exclusion provided by this section applies to the initial purchaser who purchased the new building from the owner-builder only if the owner-builder did not receive an exclusion pursuant to this section for the same rain water capture system and only if the initial purchaser purchased the new building prior to that building become subject to reassessment to the owner-builder, as described in subdivision (d) of Section 75.12.

(1) The initial purchaser of the new building shall file a claim with the assessor and provide to the assessor any documents necessary to identify the value attributable to the rain water capture system included in the purchase price of the new building. The claim shall also identify the amount of any rebate for the rain water capture system provided to either the owner-builder or the initial purchaser.

(2) The assessor shall evaluate the claim and determine the portion of the purchase price that is attributable to the rain water capture system. The assessor shall then reduce the new base year value established as a result of the change in ownership of the new building by an amount equal to the difference between the following two amounts:

(3) The extension of the new construction exclusion to the initial purchaser of a new constructed new building shall remain in effect only until there is a subsequent change in ownership of the new building.