Hello, hopefully someone can help me out.

Ok so I Put up 1inch extruded polstyrene and glued it to the wall. framed up my 2x3wall, not yet anchored down. Couple questions before I go any further.

1.What was supposed to be done at the top of a framed wall running parallel with the floor joists? as far as fire codes go. I have a two inch gap. I slid the xps up behind the floor joist to the subfloor. That covered 1 inch, the top plate will cover the other. is this going to be ok? Also do firebreaks absolutely have to be used inbetween studs extended to concrete?

2. What about the parallel joists? I am thinking of cutting smaller squares above the top plates and just gluing them in. Then when I cut the full sheets for the other wall notch around the joists to subfloor. ????essentially double insulating.

3. What, if anything, should be used on seams around the xps, like floor and in corners? would some caulk do anything? and is duct tape ok to use to tape the joints with?

4.I plan on adding 2 1'/2 inch xps for additional insulation in between studs and just sectioning to allow for running electrical. yes/no?

I have looked through every page and I am still a bit confused, never seems to be a defenite answer.