Thanks Dennis & all others who responded,
The project is in the desert, just outside Phoenix. It appears I should be
considering a 2x8 for such a long extension. The soffit will attach to the
bottom edge so it will have some bracing. I'm not sure yet what the soffit
material is made out of.
I've seen many 5' to 7' eaves - all with problems. Remember to consider the
effects of creep. In a year of so there will be no way to insure that the
eave won't form a very unsightly edge as the eaves dip. Also, consider the
uplift on the eave and make sure that this does not become a problem.
Living in the desert, long eaves are fairly common but so are the complaints
that go with them. You might want to explain this to the client and find
examples in your area of the problem I just described.
Richard Lewis, P.E.
Missionary TECH Team