radiant floor heating on exsiting slab in the NE US? please help. Home › Forums › Archives › Old Bulletin Board Archives › radiant floor heating on exsiting slab in the NE US? please help. This topic has 1 reply, 2 voices, and was last updated 25 years, 4 months ago by troy. Viewing 1 reply thread Author Posts 5 May 1999 at 9:36 am #282521 Natty Boe how to install radiant floor heat on exiting slab in basement with exsisting gas hot water heating system ?please help with profesional advise .NEASTERN electrician/homeowner.thanks. 12 May 1999 at 2:34 am #306175 troyParticipant Check this article in Fine Homebuilding. Its the most comprehensive Ive seen in my research for mods to an older house Im about to start on.Jim Author Posts Viewing 1 reply thread The forum ‘Old Bulletin Board Archives’ is closed to new topics and replies.