A diagonal support brace for a screened enclosure of the type having a plurality of laterally spaced apart frames extending over a recreational area. For preferred embodiments, the irradiation wavelength is between 900\u2013930 nm, 1190\u20131220 nm, 1700\u20131730 nm, or 2280\u20132350 nm. The flexible sealing finger is received within a sealing chamber formed as part of the rim.