Condominium Administration Act Building Administration Division Article 12

The reparation costs for common walls, building floors or the plumbing and wiring therein shall be shared by the unit owners sharing the common wall or building floor. However, reparation costs incurred due to causes attributable to a unit owner, the expenses shall be paid by such unit owner.
中文原文 公寓大廈管理條例第12條
專有部分之共同壁及樓地板或其內之管線,其維修費用由該共同壁雙方或樓地板上下方之區分所有權人共同負擔。
但修繕費係因可歸責於區分所有權人之事由所致者,由該區分所有權人負擔。

English translation for reference only; the Chinese text prevails. Not legal advice.