The Facade Is Where Buildings Go to Stall
On any building with a curtain wall or glazed facade, the most failure-prone interface is the one between the structural steel that carries the building and the curtain wall system that closes it in. They're designed by different people, fabricated by different companies, and reviewed by different engineers — yet they must meet at literally millimetre-perfect coordinates.
When anchoring coordinates, embed plates, and erection tolerances don't line up, the facade crew arrives to find the steel is 25 mm off where the curtain wall drawings assumed — and the job stops while the whole sequence is redesigned in the field.
“The curtain wall doesn't fail because of bad materials. It stalls because the steel and the glazing were designed, drawn, and reviewed without ever agreeing on the coordinates where they meet.”
The Steel Scope
Embed plates, anchor bolts, spandrel beams, and the structural frame the facade attaches to.
The Curtain Wall Scope
Mullions, anchor clips, glazing pockets, and the shop drawings that locate every member.
Where the Coordination Actually Breaks
Anchors vs. the steel that carries them
The curtain wall's shop drawing locates its anchor clips on the steel flange. But the steel embed and bolt locations are set by the steel shop drawing — reviewed separately. If the two never reconcile, nothing lines up.
Erection tolerances baked in too late
Steel moves during erection — columns lean, spans drift. The curtain wall absolutely depends on those tolerances being respected in the design. If the facade drawings assume perfect steel, the field pays the difference.
Shop drawings reviewed in isolation
The steel fabricator's drawing and the curtain wall supplier's drawing each get 'approved' on their own. The reviewer who checks them as a matched set — that's who prevents the clash.
Thermal movement and loads ignored
Curtain walls must accommodate the building's structural movement and wind load without cracking the glazing. That requires the engineer to connect the two systems' requirements, not just two drawing boxes.
The Cost of Getting It Wrong
The visible symptoms are dramatic: anchor clips burning through a facade crew's week while steel plates get field-welded to correct positions, glass units sitting stacked in a laydown yard because their opening moved, and a critical-path facade slippage eating weeks — all while the building's weather-tight date (and its occupants) waits.
And it's rarely fixable quickly: replacement glazing units are fabricated to order on long lead times, and re-drilling anchor connections on an installed steel frame is structural rework no one wants to own.
May Engineering Inc: The Coordinator Between Systems
This is exactly the kind of project May Engineering Inc's shop-drawing and coordination services exist for. We take the structural steel drawings and the curtain wall / glazing / cladding shop drawings together, check the anchors against the framing, reconcile the tolerances with the structural engineer, and resolve the clashes while they're still lines on a PDF — not steel in the field.
Managing a building with a glazed facade or heavy shop-drawn components? Put the coordination review in place before fabrication — it's the cheapest schedule insurance your project can buy.
Steel and glazing clashing on your project?
May Engineering Inc coordinates structural steel and curtain wall shop drawings across Ontario — keeping facades on schedule, not in the laydown yard.
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