I have shown option 3 but given the 24 stemwall and the 12 projection of the stemwall above the 4 slab it would seem more practical to go with option 2.
How to fill in garage door opening.
Attach the sole plate with masonry nails or with lag screws inserted into pre drilled holes in the slab.
Plan to add wooden framework to fill the empty space.
The fact that the door is in the middle means that both sides of the wall around the door have to be kept clear and no furniture can be placed along that wall.
Draw the house with its present exterior materials.
Headers should be a minimum of 12 wide.
It is so surprising how a room can be made much larger simply by moving a door from the middle of a wall to the end.
This lumber will be used to attach your garage door track and a portion of your assembly.
Construct a new sole plate across the opening.
Plan to add wooden framework to fill the empty space.
Add 2 by 4 inch framing boards on 16 inch centres to fill in the wall area.
Doubled 2 4 s at minimum should be at each edge of the garage door to allow for the mounting of the tracks and jamb brackets.
Use treated lumber rated for ground contact and insert a strip of aluminum or copper termite shield between the wood and the slab.
Header requirement 2 at minimum the header should be 12 wide with doubled 2 4 at opening and ceiling running the width of the door with a 2 4 in the center of the opening for the center bracket to attach to.
This would be a typical application with portal frames each side of the garage door.
That hanging plastic was there just to block the wind some and keep the debris outside.
Cut two 2 x 6 pieces of lumber and attach to the face of the wall running from the edge of your garage door jambs to the ceiling of your garage.
Take down the garage door and tracking before you implement the framework plan.
Pull a measurement from the floor of your space to the ceiling next to the door opening.
A confused student is a good student.
He started by ripping out the old door door frame and the flimsy insulation leaving a giant hole in the house.
We decided to do a wood frame wall rather than a stone or masonry wall for one main reason.
Take down the garage door and tracking before you.
The end of day one was looking a lot like this.
Sketch the curbside view of the door space in various ways.