I am managing a small Casita build (20 x 20) in AZ and our plans call for a 3:12 pitch with a 1′ eave on all sides. On two sides we are adding a 2×8 corbel detail under 1/2″ cdx ply (as per plans). My question on this is – is the 1/2″ sheathing enough dimension over the 2×8 corbel or do I need to do thicker sheathing?