Insulation and other energy conservation measures hereafter added to
one, two, three or four family homes, which qualify for (a) financing
under a home conservation plan pursuant to article VII-A of the public
service law, or (b) any conservation related state or federal tax
credit or deduction heretofore or hereafter enacted, shall be exempt
from real property taxation and special ad valorem levies to the extent
of any increase in value of such homes by reason of such addition.