Structural Systems and Building Envelope
This domain tests recognition of structural framing and envelope assemblies, and whether you can separate visible symptoms from their causes without practicing engineering.
Structure
Common commercial framing includes structural steel with concrete on deck, cast-in-place or precast concrete, reinforced masonry, heavy timber, and light wood frame in low-rise buildings. Look for deflection, corrosion at connections, spalling with exposed rebar, diagonal or stair-step cracking in masonry, differential movement at expansion joints, and damaged spray-applied fireproofing.
Envelope
Envelope includes wall cladding, curtain wall and storefront, masonry veneer, EIFS, sealant joints, flashing, and below-grade waterproofing. Water entry usually starts at failed sealant, unflashed penetrations, or blocked weep holes. Thermal and building movement joints are normal; the question is whether they remain functional.
Worked example
A two-story brick veneer office has a stair-step crack running from a window corner toward the roofline, wider at the top. A vertical crack at a control joint is hairline and uniform. Reasoning: the stair-step pattern follows mortar joints and suggests movement at the foundation or lintel; the hairline vertical crack at a joint is consistent with shrinkage or thermal movement. Report both, describe width and location, and recommend a structural engineer evaluate the stair-step crack. Do not label it "settlement" as fact.
Traps
Diagnosing cause; calling cosmetic cracks structural; missing fireproofing loss above ceilings; ignoring sealant and flashing because the wall looks fine; and inspecting a facade without fall protection or rope/drone-access qualification.