I wouldn't build it.

The combination of a shallow pitch and a raised tie is no bueno. There will be a tremendous amount of tension where the tie meets the top chords. It would be a challenge in Georgia (no snow load) at that span and spacing even using a lot of steel in the connections.

You should really have that looked at by a PE before it gets worse.

Where is the project?
What species of timber?
Are you the owner, builder, carpenter, designer, none of the above?
Are there other options, like a structural ridge running the length of the room and common rafters (biguns)? Should work if the room is really short.