dishwasher conversion Home › Forums › Public Forums › Estimating & Costing › dishwasher conversion This topic contains 1 reply, has 2 voices, and was last updated by rkennedy 12 years, 6 months ago. Author Posts 24 Apr 2007 at 4:01 pm #279621 MasterPlumbersKeymaster What needs to be done to add an undercounter dishwasher to a 1954 home and how much would this cost? I live in Madison, WI. Thank you! 1 May 2007 at 11:57 pm #301323 rkennedy hot water supply line ; 30 in. under counter space.120v power supply. Air gap fitting on drain line. 1.5 in. y on k – sink strainer.” go badgers.” I’m in Madison too. Author Posts You must be logged in to reply to this topic.