Partially wooden windows:

Partially wooden windows:

Partially wooden or combined frames from the outside (street part) are made of cheaper material, such as plastic or aluminum, while the inside (entering the room) is made of wood. Such windows are generally good, as they absorb the positive characteristics of the two types of material, but they are prone to passing water, which leads to decay from the inside of the frame. Thus, this type of windows should be installed correctly using a waterproof membrane and other ways to minimize moisture concentration.