An aluminum-clad window is a wooden window that is covered with aluminum to protect the wood from the elements. The windows are manufactured as wooden windows and then subsequently treated with aluminum. This process not only helps shore up the structure of the window but is also effective in preventing the window from warping and being susceptible to weather-related deterioration. Aluminum-clad windows often are available in a number of styles and colors. Additionally, they are available with double and triple-panes, which helps make your home more energy efficient. Cost-wise, aluminum clad windows are slightly more expensive than other types of windows, such as PVC-clad or all-wood windows. However, they offer lower maintenance costs as well as reduced energy costs due to their energy-efficiency. Each manufacturer of aluminum-clad windows uses a slightly different process though primarily the process is the same: Create a wooden window and shore up the frame with aluminum facing.