Originally Posted by jogr
There is also a way to stick frame the roof that doesn't require a load bearing ridge beam. It just uses a ridge board - but I'm not a pro framer so I can't give you details on how it is done. Maybe someone else on here is familiar with this technique.
Roofs steeper than 3/12 pitch can be framed with a ridge that is essentially non-structural. The rafters must be tied together with low collar ties or ceiling joists however. These ties prevent the rafter heels/posts/walls from thrusting outward under roof load.
2x4's in the house's wall can certainly support the load. What you need to do is have the assistance of a design professional. Although two 2x4's are all that would directly support the ridge, it might require 6, 7, 8, or more studs to stiffen the bearing members. It all depends on load and structural reactions.