Typical framing materials include wood, vinyl, aluminum, fiberglass, and composites. Manufacturers often combine materials to use the best features of each. For example, a variation of the wood-framed window is to clad—or cover—the exterior face of the wood frame with either vinyl or aluminum, creating a weather-resistant surface. Clad frames have lower maintenance requirements, while retaining the attractive wood finish on the interior. Although great for safety, sound protection, and aesthetics, frames with high insulation value are not as important for most Florida homes, but the frame material should be thermally non-conductive, and the whole window will ideally have an AL (Air Leakage) rating of 0.30 or less.

Learn more about thermal breaks and frames at http://www.efficientwindows.org/technologies.cfm.

Additional Resource

UF IFAS Energy Efficient Homes: Windows and Skylights - http://edis.ifas.ufl.edu/FY1045