I just recently brought a old house that seem to have ponds of waters on the modified bituman. And i can see the modified bituman has rust stains on it. The area seem to have created a slope that is holding the water.
I assume it was done with cold adhensive as I see a 5 gallon bucket of it.
The question i have is should I put another layer of modified bituman on top of the old bituman or should I take the layer out and redo it?
Also what is the best way to create a flat surface?
Mod bit doesn't take to ponding well at all.Positive drainage must be acheived.Yes you can go over it,but this will not solve you problem.If possible post some pics.I don't know if this answered your question but regardless you cannot have ponding.