Why you should never pour boiling water down the sink

You've just cooked pasta or blanched vegetables and need to get rid of a pot full of boiling water.

Why you should never pour boiling water down the sink

TL;DR

  • Boiling water can damage plastic pipes not rated for high temperatures (above 60°C).
  • The thermal shock from sudden temperature changes can cause pipes and porcelain sinks/toilets to crack.
  • Repeated exposure to boiling water can soften, deform, or crack plastic pipes, leading to leaks.
  • Hot water causes pipes to expand and contract, weakening joints over time.
  • The risk of damage is higher in colder temperatures when pipes are already cold.
  • To avoid damage, cool the water before pouring it down the drain or run cold water simultaneously.
  • Using sink strainers to catch food scraps and avoiding pouring grease, coffee grounds, pasta, or potato peels down the drain are recommended preventative measures.