Hi, I am framing a wall in a basement room, to finish off the room. The sill plate is on top of the wall, and between the sill plate and the wall there is some type of flashing, looks like zinc. It juts out from the sill plate and is preventing the 2 x 4's from going flush with the wall. It has some flexibility and I can probably bend it back out of the way. Is this okay to do? Should I caulk between the sill plate and the wall since I will be putting in a ceiling? What is the flashing for? The other sill plates in the house do not have it. Thanks.
Okay to bend it back?
Yes, it should be.
Should I caulk between the sill plate and the wall?
No, but you could caulk at the interface of the sill plate and the flashing if it is a potential for air infiltration.
What is the flashing for?
Hard to say without seeing the outside and since it's in one area only.