Seal the Deal

Water finds every weakness. Wind makes it worse. In a Miami-Dade hurricane, rain doesn't fall - it flies sideways at 180 mph. Proper flashing and sealants create multiple lines of defense that keep water out even when individual components fail.

Get Waterproofing Specs

Wind-Driven Rain Simulator

MPH Wind

IN/HR Rain

PSF Pressure

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Water Intrusion

BLOCKED

Wind Speed 0 mph

The Right Sequence Matters

Flashing must be installed in the correct order - each layer sheds water to the layer below.

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Sill Pan First

Install sill pan with end dams. This catches any water that gets past the window and directs it outside.

📐

Jamb Flashings

Jamb flashings overlap sill pan by 2+ inches. They protect the vertical edges and shed water onto the sill.

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Head Flashing

Head flashing overlaps jambs by 2+ inches. It's the first line of defense, shedding water to the sides.

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Seal the Gaps

Sealant at flanges and WRB laps. Remember: sealant is backup - geometry should work without it.

Multiple Lines of Defense

Miami-Dade's extreme conditions require redundant protection systems.

🛡️ Primary Defense

The exterior cladding (stucco, siding, panels) deflects most rain before it reaches the building structure.

Stops 90% of water

Weakness Joints & Penetrations

🔄 Drainage Plane

Weather-resistive barrier (WRB) and flashings create a continuous drainage path that directs water out.

Critical At Transitions

Overlap Required 2" minimum

🔒 Air Barrier

Stops pressure-driven infiltration. Wind creates pressure that pushes water through tiny gaps.

Pressure Up to 72 PSF

Gap Tolerance 1/64" max

Frequently Asked Questions

Common questions about flashing and sealants in Miami-Dade

Flashings fail when wind pressure drives rain horizontally or even upward against normal drainage paths. At 180+ mph, water doesn't just fall - it's propelled with tremendous force into any gap. Proper flashing design accounts for these extreme pressures with multiple defense layers and pressure-equalized details.

Wind-driven rain in Miami-Dade HVHZ can exert water pressures equivalent to 8-10 inches of standing water (about 4-5 PSF). This pressure forces water through gaps as small as 1/64 inch. Flashing and sealant systems must be designed to resist these pressures while allowing for thermal movement.

Window flashings must be installed in the correct sequence: sill pan first with end dams, then jamb flashings overlapping the sill, then head flashing overlapping jambs. Each layer sheds water to the layer below. Sealants are secondary - the geometry must work even if sealants fail.

Yes, sealants in Miami-Dade HVHZ must meet specific standards including AAMA 800 for sealant selection and TAS 204 for installation. They must maintain adhesion through thermal cycling, UV exposure, and hurricane conditions. High-movement silicone or hybrid sealants rated for +/-50% movement are typically required.