There are two design paths in facade engineering: custom engineered systems and off-the-shelf tested systems. Custom is simple to explain - everything gets engineered. Glass, framing, connections, anchorage, all of it is unique, so all of it gets analyzed.

Tested systems are where projects get into trouble. Manufacturers test their systems for frame strength, deflection, and air and water performance across a range of configurations, per ASTM E283, E331, and E330. If your project uses the system within its published limits, a lot of it can be accepted by comparison to the tested configuration. That is real value and I’m not knocking it.

But the test report doesn’t cover the whole job. A few things always need project-specific engineering:

Other common ones: structural analysis of glass infill, transitions between systems, and odd panel configurations. If it is outside what was tested, it gets engineered.

A tested system is only as good as its connection to the building. The facade engineer’s job is to make sure the complete system meets the project’s demands, not just the extrusions that went in the test chamber. Use the manufacturer’s data within its limits. Don’t skip the engineering where the system meets the building.

Working with a tested system and not sure what needs a stamp? Send us the drawings and we’ll tell you what is covered and what isn’t.