I guess I stumped everyone but Bob.
Here’s what I ended up saying:
"The single wythe split-face block wall at the front of the building has no apparent system to prevent water entry. It is an exceptionally porous type of wall system. No drainage plane or weep holes were apparent and the interior cells of the block wall probably were not designed to shed the water which naturally and easily penetrates the block. Effloresence visible on the interior of the block wall, above the ceiling, indicates that moisture migration through the wall occurs. And there was no indication of the application of a water repellent to the exterior surface of the block. Where water proofing is applied, it generally requires a re-application every 3 to 7 years. Moisture wicking into the block may be trapped in the cavity between the block and the sheetrock, a condition conducive to mold growth behind the sheetrock walls. The masonry wall was also in contact with soil, which is another source for water migration through the wall. That interior cavity was not visible to us. Our client mentioned window leaks, but we suspect the leak is actually due to the wicking of water through the block, as the windows appeared to be generally well sealed. With a lack of weep holes (at the main building–they were present at the addition), any water entry into the cavity holes can drain as easily into the building as out of it. We observed no interior moisture present on the day of the inspection, and we also could not view behind the sheetrock. We recommend an evaluation of the wall structure and water proofing methods by a licensed general contractor familiar with the construction of split face concrete masonry walls.
The concrete masonry wall at the front of the building may have moved, as a large gap was present between the metal siding at the left side and the front wall. This provides a path for water entry and should be sealed at the minimum. We suggest that you have a licensed general contractor ensure that the wall is properly anchored to prevent lateral movement."