Valmiki Ramayana Ayodhya Kanda Sarga 105 Shloka 18

दृढस्थूणम् with sturdy pillars, आगारम् house, यथा as, जीर्णं भूत्वा after getting dilapidated, अवसीदति decays, तथैव in the same way, नराः people, जरामृत्युवशंगताः under the sway of old age and death, सीदन्ति are destroyed.

Even a house constructed with sturdy pillars gets dilapidated and ultimately decays. In the same way people under the sway of old age and death are destroyed (at last).