Additions or improvements to property
(5) Additions or improvements to property(i) Additions or improvements substantially affecting nature of property. If an addition or improvement is made to property a term interest in which was valued under paragraph (c)(1) of this section, and the addition or improvement affects the nature of the property to such an extent that the property would not be treated as property meeting the requirements of paragraph (c)(2) of this section if the property had included the addition or improvement at the time it was transferred, the entire property is deemed, for purposes of paragraph (c)(4) of this section, to convert (effective as of the date the addition or improvement is commenced) into property a term interest in which would not qualify for valuation under paragraph (c)(1) of this section.