Horizontal Crack at the Second-Floor Rim
A 1986 two-story apartment building has a 120-foot-long three-coat stucco facade. A horizontal crack runs about 20 feet along the second-floor rim line; width is 1/8 to 3/16 inch. Rust-colored staining follows the crack, and a 1/2-inch outward bulge is visible over an 8-foot section. There are no control joints on the facade. Diagonal cracks radiate from several window corners. Moisture readings near the crack are 20 to 24 percent, versus 12 percent at a control location. The owner says the crack has been there for years and asks whether it is just stucco shrinkage that can be patched and painted before sale. The inspector has no structural engineering license.
1. Is this most likely shrinkage cracking or something else? What specific observations drive your judgment?
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The pattern does not look like ordinary stucco shrinkage. Shrinkage cracks are usually fine, map-like, and not accompanied by a 1/2-inch outward bulge. This crack is horizontal at the second-floor rim line, 20 feet long, 1/8 to 3/16 inch wide, with rust staining and a bulge. That combination suggests movement or deterioration at the floor-line framing or sheathing, possibly corrosion of framing connectors or lath, or differential movement of the wall. The diagonal cracks at window corners add to the concern. The moisture readings near the crack are elevated, so water entry may be contributing. I would not call it cosmetic. I would describe it as a sign of possible structural or moisture-related movement and recommend further evaluation.
2. What are the limits of your inspection, and what further evaluation do you recommend?
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My inspection is visual and moisture-meter based; I cannot determine the cause or structural significance without exploratory openings and engineering analysis. I would recommend a licensed structural engineer evaluate the bulge, the floor-line framing, and the window-corner cracks, and a stucco contractor open the wall at the crack to inspect lath, sheathing, and framing. I would state the limits clearly: no interior wall cavities were opened, no engineering analysis was performed, and the moisture readings are relative. I would also recommend checking the roof and flashing above, because water may be feeding the corrosion or movement. The owner should not patch and paint before the cause is understood.
3. Draft report language that is clear but not alarmist, and explain why patch and paint is not appropriate.
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A defensible report would say: A horizontal crack approximately 20 feet long and 1/8 to 3/16 inch wide was observed at the second-floor rim line, with rust-colored staining and a localized outward bulge of about 1/2 inch. The cause was not determined. The condition is beyond cosmetic shrinkage and warrants evaluation by a licensed structural engineer and exploratory opening by a qualified stucco contractor before repair. That language is clear without declaring the building unsafe. Patch and paint is inappropriate because it hides the movement and can trap moisture; it does not address the cause. I would recommend monitoring only as an interim step, not as a substitute for evaluation.