It will depend on several factors and what your GH residents need.
If the plants need high humidity and the outside air is expected to be dry, then opening the double doors might be a problem. You do lose some humidity through the vents and exhaust already, but opening the doors will speed up the humidity loss.

If the outside/inside humidity difference is not that significant (or is not a problem) then the doors can be opened in order to equalize the temperature.
The GH can then act as a fancy shadehouse :)

I do open my GH doors (orchids) during days when the temps exceed 90F. But humidity is usually not that bad in summer here 40%-50%.

I hope this helps
~John

Our area is humid (SE Virginia). Thanks

Troy

That should be ok then. Your GH can double as a shadehouse during the warm days.

Great! Now I don't have to build anything.