Exterior and House Building Type Few architects changed the face of Fire Island as much as the midcentury master Horace Gifford. In 1975, he created this geometric glass "tree house" on Sail Walk, which sports screened vents between slanted glass walls and suspended floors that draw breezes through a chimney-like skylight.  Photo 2 of 6 in Take a Peek Inside a Beachside Enclave of Modernist Masterpieces