Hi John, we are now putting the second module on our Little Cabin. What is now an outside wall will become an inside wall between the the sleeping module and the new addition. Do I need to remove the vapor barrier between them? Also, I will be putting a 5' X 2 1/2' window and a door in each of the non weight bearing side walls. How thick should my headers be? 2X8? 2X10? Thanks, Bill
You can just leave the moisture barrier in place, it will not cause a problem.
The header in a non-load bearing (gable end) wall can be a double 2x6. That will span up to 6'-8".
Send a photo when you get it up. I know folks have done this but we don't have anything in the gallery yet.