length of 1/2 and 3/4 copper pipe-hot water base baord Home › Forums › Public Forums › General Plumbing › length of 1/2 and 3/4 copper pipe-hot water base baord This topic has 1 reply, 2 voices, and was last updated 19 years ago by CincinnatiPlumbing. Viewing 1 reply thread Author Posts 17 Apr 2005 at 4:01 pm #277581 DONALD BUCKHAM What can the total length of 1/2 or 3/4 in copper pipe when used with hot water base board heat(BBH). BBH is usually 3/4 pipe ,is it ok to use 1/2 or should you use 3/4. BOB 18 Apr 2005 at 4:34 am #296609 CincinnatiPlumbingParticipant Going by memory here…… I believe it is 25 feet on 1/2″ and 65 or 70 feet on 3/4″ Author Posts Viewing 1 reply thread You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In