In residential plumbing, brass, copper, and cast-iron closet flanges have largely been replaced by ABS and PVC flanges. Other than that, today's closet flanges look essentially the same as those made 50 years ago.
They also suffer from many of the same problems. And when closet flanges break or are improperly installed, toilet bowls can rock and shift position, allowing water to leak out and foul gases to escape. This can lead to structural damage and unsafe and unsanitary conditions.
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