This is the frame that I'm using for my sukkah. In the event that the bars forming the frame's roof cannot be removed, would they completely posul the flat sechach I might construct beneath them? If so, what considerations must be undertaken in order to construct a sukkah with a slanted roof? My understanding is that a slanted roof does not posul the sukkah but that, aside from not being optimal, there are complications to consider. I cannot seem to find a source which addresses these complications, though. Obviously, my preference would be if the four bars forming the roof just didn't posul it in the first place. This seems unlikely, though.
Sounds to me like Shulchan Aruch 626:3:
See also Rama and Mishna B'rura there, or your favorite nos'e kelim. But as this is for you a practical matter, CYLOR.