2-part door for raised patio (horizontal and vertical) with tiles possible?
Your idea is possible. It will take as you may know already, a custom metal fabricator who is certified, to build to insure all welds will hold up under the weight of the assembly, since it will weigh hundreds of pounds. Using aluminum to make the base, sealed bearings in proper housings for the pivots. Counterbalance filled with lead to ease its operation, and solution to help lower the door in place to keep it from slamming down, like a gas filled piston and rod, like a shock absorber. an aluminum mesh, spot welded in many places to give a way for the tile to bond to the plate that makes the face of the door, with a perimeter angle to dress up the edge so you do not see all the layers at the edge of the door. With all this done, it will need to be powder coated to keep the contact with cement based products separated, so it will not corrode. Your biggest problem will be with your counter balance. When the door raises, it will drop in front of the door. It may be better to use springs or electric lift mechanism, or hydraulics. I made a small sketch to see how it acts together with a counterbalance.


This is by no means a complete sketch, it is missing reinforcements, the hinge pivot is off,etc. Just a picture study on feasibility.

In my opinion a lift system like that is on the rear gates of SUV's is a good way to go, although, should one of them fail....