@Christopher Smith, you are correct. Here are the regultatory examples for your reference:
Example 13. Not a betterment; new roof membrane
M owns a building that it uses for its retail business. Over time, the waterproof membrane (top layer) on the roof of M's building begins to wear, and M began to experience water seepage and leaks throughout its retail premises. To eliminate the problems, a contractor recommends that M put a new rubber membrane on the worn membrane. Accordingly, M pays the contractor to add the new membrane. The new membrane is comparable to the worn membrane when it was originally placed in service by the taxpayer. Under paragraphs (e)(2)(ii) and (j)(2)(ii) of this section, an amount is paid to improve a building unit of property if the amount is paid for a betterment to the building structure or any building system. The roof is part of the building structure under paragraph (e)(2)(ii)(A) of this section. The condition necessitating the expenditure was the normal wear of M's roof. Under paragraph (j)(2)(iv) of this section, to determine whether the amounts are for a betterment, the condition of the building structure after the expenditure must be compared to the condition of the structure when M placed the building into service because M has not previously corrected the effects of normal wear and tear. Under these facts, the amount paid to add the new membrane to the roof is not for a material addition or a material increase in the capacity of the building structure under paragraph (j)(1)(ii) of this section as compared to the condition of the structure when it was placed in service. Moreover, the new membrane is not reasonably expected to materially increase the productivity, efficiency, strength, quality, or output of the building structure under paragraph (j)(1)(iii) of this section as compared to the condition of the building structure when it was placed in service. Therefore, M is not required to treat the amount paid to add the new membrane as a betterment to the building under paragraph (d)(1) or (j) of this section.
Example 15. Not replacement of major component or substantial structural part; roof membrane
L owns a building in which it conducts its retail business. The roof decking over L's building is covered with a waterproof rubber membrane. Over time, the rubber membrane begins to wear, and L begins to experience leaks into its retail premises. However, the building is still functioning in L's business. To eliminate the problems, a contractor recommends that L replace the membrane on the roof with a new rubber membrane. Accordingly, L pays the contractor to strip the original membrane and replace it with a new rubber membrane. The new membrane is comparable to the original membrane but corrects the leakage problems. Under paragraphs (e)(2)(ii) and (k)(2) of this section, an amount is paid to improve a building if the amount is paid to restore the building structure or any building system. The roof, including the membrane, is part of the building structure as defined under paragraph (e)(2)(ii)(A) of this section. Because the entire roof performs a discrete and critical function in the building structure, the roof comprises a major component of the building structure under paragraph (k)(6)(ii)(A) of this section. Although the replacement membrane may aid in the function of the building structure, it does not, by itself, comprise a significant portion of the roof major component under paragraph (k)(6)(ii)(A) of this section. In addition, the replacement membrane does not comprise a substantial structural part of L's building structure under paragraph (k)(6)(ii)(B) of this section. Therefore, L is not required to capitalize the amount paid to replace the membrane as a restoration of the building under paragraph (k)(1)(vi) of this section.
