I am renovating a cinder block barn built in the early 1950's. I need to cut a 8' x 8' opening in the gable ends of the structure for a new doorway. From the ground to the ridge is about 16' feet. I am concered the block above the opening may fall before I can get a micro lam haeder in place. There is no way to temporarilly support the block. Anyone have any suggestions or should I be concered the block may give in? I thought about inserting the micro lam as I remove one block at a time, then remove the lower courses starting from the middle of the opening and place a temporary post in the middle and move further out with the post as I remove the perimeter courses.
If you are thinking of supporting masonry with a wood beam, you better hope you do not (or ever expect to) have to meet any kind of a code.
You never said how big or how high the walls are.
The best approach would be to use a steel beam that will not warp or deteriorate due to exposure if it is an exterior wall. I assume the gable wall carries little load outside of the masonry above and some roof load unless there are some second floor beams perpendicular to the wall that could increase the load.
Since this is a new opening, you can expect some movement/cracks unless you do a good job or supporting the wall and loads from above.
There methods that are commonly used for supporting masonry and associated loads, but they are not usually DIY projects since they take experience.