Rain Jacket Flashing Systems is a revolutionary new replacement window flashing installation technique that utilizes specific components to pre-flash the existing window opening, without removing the existing cladding when installing replacement windows. Our patented replacement window flashing installation has been tested at an AAMA certified lab and field tested with many different cladding systems. It has surpassed all testing guidelines with its ability to resist water and air penetration. With the advent of new building codes the Rain Jacket Flashing System meets all requirements of new code without removing existing cladding. This includes sill pans, jamb flashings, head flashings, membranes, and integration to the building envelope, as well as drainage over the cladding if necessary.