Pursuant to § 459 of the Real Property
Tax Law, an improvement to any real property used solely for residential
purposes as a one- , two- or three-family residence shall be
exempt from taxation to the extent of any increase in value attributable
to such improvement if such improvement is used for the purpose of
facilitating and accommodating the use and accessibility of such real
property by a resident owner of the real property who is physically
disabled, or a member of the resident owner's household who is physically
disabled, if such member resides in the real property.
Once granted, the exemption shall continue on
the real property until the improvement ceases to be necessary to
facilitate and accommodate the use and accessibility of the property
by the resident who is physically disabled.