Before you can start putting wood down on the trusses, you need to nail the facia board
on the end of the truss tails. The tails of the trusses are the boards that extend past
the walls and help form the overhang that most houses have.
Here are the roof trusses with some of the sheets of OSB on them.
The facia board goes on the end trusses so that when you look at the front of a house,
you see a solid board across the end of the trusses. Do not put the facia board even
with the top of the truss tail as when you put the plywood down on the truss, the plywood
will go past the end of the truss onto the facia board. If the facia board is even with
the top of the truss tail, it will force the plywood up off the truss. This is because the truss
board that you are nailing the plywood to is at an angle, so in order to keep that same angle,
you need to lower the facia board below the top of the truss tail.
Here is a view from below. You can see the opening at the peak for ventalation.
Once the facia board is on, you can start putting on the plywood. Between each row of
plywood, make sure you have plywood clips to help hold all the sheets of plywood together.
Leave some room at the top if you are planning to install any sort of ventilation system.
You need to put tar paper down before you can put the shingles down. The tar paper will help
prevent any water from getting into the attic should water happen to get through the shingles.
Depending on when you plan to shingle the house, you may want to use a heavier weight tar paper.
We used 15 pound tar paper and it did not last the two months that we needed it to last. In
order to keep all of the other contractors moving, we needed to get back down on the bottom
of the house to put up the rest of the walls, the outside sheating, tyvek, etc. The tar
paper that we used lasted for about a month before it started ripping, after that about once
a week, we had to replace a piece or two of tar paper. When we first put the tar paper down
we put 2x4's diagonally across the roof which did help quite a bit. We probably would have lost
more if it wasn't for those.