Coal tar tie in

Got a repair on a coal tar roof that will require a square or so of roof and some wall flashings. I have CT cement in 5 gal buckets, be I’m curious if anyone here has experience with mod bit, epdm, or tpo, tie-ins

When I have to tie into odd stuff I just use metal to separate the two.

Good idea. Problem is that it gets brittle when cold, and metal moves when it’s cold. Wasn’t sure if neoprene would work. Coal tar is a pretty impressive system from what I’ve seen. Not many people know about it, and if they do, they seem to be afraid of it.

Coal tar will destroy most other roof membranes it makes contact with over time. Only tie in asphalt products unless it is temporary. Coal tar is the best flat roof ever made hands down, but the stuff will eat you up.