SubRay is Watts Radiant's new way to sandwich radiant tubing in a low-profile subfloor. With SubRay, an installer secures ASTM standard 3/8" or 1/2" radiant tubing at two opposite sides of a room with cabinet grade, 11- or 17-ply Baltic Birch header sticks. Between these are "sleepers" that organize the tubing into two-inch-wide radiant channels that are spaced on eight-inch centers. Beneath the tubing is aluminized Mylar tape that reflects energy upward to an aluminum diffusion layer that extracts heat closest to the floor surface, spreading warmth to the entire finished floor. With wider channels, a SubRay floor makes no noise from expansion and contraction of tubing. The tubing lies freely in broad channels, requiring no adhesives. Watts Radiant.