Clear Choices for Windows | This Old HouseMaterial Choices Windows frames come in a number of different materials, including wood, vinyl aluminum, fiberglass and composite plastic. Vinyl-frame windows are the most affordable as little as half the price of comparable wood-frame versions. They're also especially energy efficient, thanks to a honeycomb of chambers that boost insulating ability by trapping air, and can be built to fit any size opening. And unlike wood, they never need repainting, though colors are limited.