Interactive decision tree to determine your glazing requirements
1
Is this for a tornado storm shelter or safe room?
Do you have FEMA P-361 requirements or need to reference the ICC 500 standard?
⚠️ We Cannot Help With Storm Shelters
Standard architectural glass cannot be used in tornado shelters. All glazed openings must be protected by tested and certified impact-protective systems designed to resist both extreme wind pressures and high-velocity debris impact.
Requirements: The whole system must be tested and certified together, including exactly how it is to be installed into the building.
Exception: This means we can only assist if you've already completed all testing and can provide exact glass makeup specifications.
2
Are you asking about tornado load requirements for ASCE 7-22?
This applies to non-storm shelter buildings that need to meet tornado load requirements.
ℹ️ Outside Our Scope
This guide specifically covers ASCE 7-22 tornado load requirements for non-storm shelter applications.
3
What is your building's risk category?
Essential facilities have higher requirements than standard buildings.
ℹ️ Standard Buildings
Category I and II buildings typically do not require tornado-resistant glazing under ASCE 7-22. Please consult with a structural engineer to confirm.
4
Is your building located in the tornado-prone region?
Check if your building is located in the gray area on the tornado map.
ℹ️ Outside Tornado Zone
Buildings outside the tornado-prone region typically do not require tornado-resistant glazing.
✅ Level D Impact Rated Glazing Required
You answered YES to both questions, so you need Level D impact rated glazing system.
Next Steps: Find a framing system certified to hurricane level D and use the glass specified in that system.
Type your building address into the ASCE hazard tool above
Figure out your plan area (rough estimate of the building footprint in sqft)
Find the wind speed from that web link for:
1700 year (Category III), OR
3000 year (Category IV)
Check: Is this number greater than 150 mph? (it probably won't be)
✅ Use Level D Impact Rated Glazing System
Next Steps: Find a framing system that has been certified to hurricane level D and see what glass they used in that system, then order that glass from Tristar Glass.
Next Steps: Find a framing system that has been certified to hurricane level E and see what glass they used in that system, then order that glass from Tristar Glass.
Typical Interlayer:
• 0.180" SG interlayer, OR • 0.154" VS02 interlayer
