After the trusses are installed the next step in building a house is sheeting the roof. When roof sheeting is installed and nailed to the trusses it greatly increases the strength of the whole house. It is like adding a cross bracing to a fence gate.
The facia is the board at the eve of the house. The facia is put on before the sheeting is put on. The framer measures out from the wall and marks a truss tail at each end of the facia board. Then he pulls a chalk line between the two ends and marks all the trusses in between. Each truss tail is cut off at this line. Now theres is a straight line of cut truss tails to nail the facia to. This makes for straight roof lines.
Blocking is installed in between each truss and on top of the bearing walls. Truss blocking strenghtens the roof system.
After the facia is installed and the valley over builds are framed the sheeting is installed. It is common to start at the facia and work your way up to the ridge of the house.
The roofer is contacted and told that the roof is almost ready to be dried in with building paper.
The plumber, electrician, and HVAC contractors are notified of the progress of the house.