ASCE 7-22 · C&C · HVHZ IMPACT PROTECTION
Storm shutters & the wind loads they resist
Shutters guard openings against wind-borne debris and must resist the same Components & Cladding pressures as the opening — both suction and positive. Keep openings intact and the building stays enclosed.
HOW IT WORKS
A shutter stops debris and holds the pressure
The covering takes the impact of a wind-borne missile, then carries positive pressure inward and negative suction outward into its fasteners and the structural opening.
WHY PROTECT OPENINGS
One breached opening roughly triples internal pressure
In wind-borne-debris regions, an unprotected opening can be lost to a missile. Once air rushes in, the building reclassifies from enclosed to partially enclosed — and the internal pressure coefficient jumps.
Enclosed — openings held
Shutters keep the envelope intact, so the design stays enclosed.
GCpi = ±0.18Partially enclosed — opening breached
A lost opening pressurizes the interior, adding to the C&C demand on walls and roof.
GCpi = ±0.55±0.55 vs ±0.18 is about a 3× internal-pressure swing — that extra suction can overload roofs and connections never sized for it.
SHUTTER TYPES
Common protective coverings
Each system must be designed for the opening’s C&C pressures — both positive and negative — and detailed for its fasteners.
Hurricane panels
Removable corrugated metal or polycarbonate panels bolted over the opening.
REMOVABLEAccordion
Side-stacking folding blades that draw across the opening and lock at center.
PERMANENTRoll-down
Slatted curtain that rolls from an overhead housing into side tracks.
MOTORIZEDBahama / colonial
Hinged louvered covers that prop outward or close from the sides over the opening.
PERMANENTHVHZ APPROVAL
Miami-Dade & Broward demand tested, approved products
In the High-Velocity Hurricane Zone, impact protection is verified by large-missile and pressure testing per TAS 201 / 202 / 203, and each product carries a Miami-Dade NOA or Florida Product Approval. Use only the approval’s rated pressures and missile class — never substitute unverified ratings.
RUN THE NUMBERS
Get C&C pressures for your hurricane protection
Size shutters and fasteners to the opening’s positive and negative design pressures — with HVHZ and Miami-Dade rules applied.