Storm Increasingly, coastal areas are requiring laminated glass that will meet impact from wind-borne debris. For applications less than 30 feet above grade, “large missile” impact standards are required. For units up to 25 square feet and design pressures up to 65 psf, laminated glass with an 0.060” (1.52mm) PVB is usually used. For applications more than 30 feet above grade, “small missile” impact standards are required. Usually an 0.060” (1.52mm) PVB is adequate. For larger and higher performance applications, thicker interlayers, a High Performance PVB or an ionomer interlayer can be required. These HP PVB and ionomer interlayers are much stiffer than standard PVB and can sustain much greater design pressures and larger sizes.