Am I required to install a garbage disposal when installing a dishwasher? Always 8% In most cases 11% In some cases 28% Never 51% Get Free Quotes Today! Question: Am I required to install a garbage disposal when installing a dishwasher? Top Answer (51% of 35 votes): Never. Answer: Never Explanation: Garbage dispoals are optional when installing a dishwasher and is not neccessary. SDL Plumbing Inc. Answer: In most cases Explanation: Other ways have a back flow drain to Dishwasher. Professsional plumbing and Handyman Services. Answer: Never Explanation: Most new dishwasher have built in disposal features Penn Builders & Installations Co, Inc Get Free Quotes From Local Pros ProMatcher Answer: Never Explanation: This isnt required however it helps. Company name here Answer: In some cases Explanation: Depending on drains, but usually not required. John's Appliance Installations Get Free Quotes Today! Find Local Pros Free Electric Appliance Installation Cost Estimates Related Questions What is the difference between a gas dryer and an electric dryer? What is a washing machine agitator? Do washing machines have filters?Top answer: Yes Does a washing machine have a transmission?Top answer: Yes Does a washing machine require GFCI protection?Top answer: Always