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Why use the Rain Jacket Flashing System

In 25 years as a window replacement contractor, we have seen hundreds of times the urgent need for a replacement window system that would not rely on sealants or foams to protect against water and air penetration. Especially at risk are wall systems with masonry claddings. Now, with the advent of new code, pressure testing requirements, and the number of lawsuits related to water intrusion around window installations it is more important than ever to consider protecting yourself and your structure from rot and mold. With the Rain Jacket Flashing System we register our replacement window flashing elements to the existing serviceable WRB (weather resistant barrier) and/or substrate and thus create a true weather tight system that will pass AAMA pressure tests!



  • Passes ASTM 1105 - E / AAMA 502 - 11 field water penetration resistance testing as outlined in Washington states RCW 64.55.050

  • Passes AAMA pressure tests equal to 120 MPH wind pushing 8" of rain per hour

  • Is accepted as a recommeded method to meet new building codes IRC R703.8 window flashing

  • Does not rely on an exterior caulking bead to prohibit water and air penetration

  • Can be integrated to an existing serviceable building envelope

  • The replacement window flashing installation may help existing water penetration problems behind the building paper by diverting water at the head flashing

  • The building owner can approach the remediation project sequentially rather than all at once, reducing upfront costs, allowing for later installation of siding. Existing replacement window installations will not pass pressure tests without the cladding and building paper being replaced

  • A true air and water tight replacement window flashing installation will maximize the efficiency of the new replacement windows

  • Can virtually eliminate callbacks from water or air penetration

  • No exterior trim is needed, allowing for maximum flexibility (or customer preference in exterior design)

  • The only replacement window flashing installation that can be used on previously retrofit windows that leak. Will pass pressure testing!

  • Can be modified for most window and door systems and sizes

  • Non-corrosive, non-conductive, and easy to cut and attach

Our System Passes Lab and Field Pressure Testing
Testing Results

Field testing video of a VPI window AAMA grade rating lc 30 tested at 3.5 psf / .673 inches of water column. Tested by QED Labs an AAMA certified testing facility



Design pressure testing was instituted in the 1940’s by a group of window manufacturers and engineers concerned

about hurricanes and other types of severe weather systems. The intent was to measure how a variety of building

products performed in these types of conditions. The design pressure tests were designed to measure wind loads

and how resistant windows and the installation would be to different types (severity) of storms. National building codes (IBC, IRC and HUD) now require testing and certification of windows and doors. Windows and sliding glass doors must meet the requirements of industry standards that include air, water and structural testing.



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