We just bought a 1922 Foursquare with a one story 18x40 cinderblock garage out back. Some time when the past owners had it they walled in the alley side of the garage with 8x16" block from the ground all the way up to the top beam in order to make it a secure workshop. Top beam is a double 2x16 if I remember right and I can't find evidence of there being a post midway along the span... a bit surprising on such a long run. The roof is a low pitch with EPDM as the material.
The goal is to open things back up – maybe a 20' opening – and install sliding barn doors. Any thoughts? If the beam is still solid I can't see a problem that will be catestrophic, although a visit from a local engineer wouldn't hurt.
We haven't moved to the house yet (living two hours away) while we do work inside. Pics are the best I have with me.