Do I need to put the building paper (15# black stuff) on the walls before I put on the rafters (so I get it up under the rafters)? I thought it might be better, but I don't want to delay the roofers if they have an opening.
P.S. I am going to close it in with soffit.
No, the paper can and should be installed after. It does NOT lap onto the top plate.
It should be installed after the roof is on.
G/L PEG