Interior window sills must be adjusted to the function and arrangement of the rooms in which they are to be installed. We can choose between wooden, stone and plastic window sills. Their width and optimal depth of the window sill in relation to the window recess should be analyzed. When choosing window sills for rooms, we usually follow their appearance and available sizes. In the bathroom, an additional criterion when choosing an interior window sill becomes resistance to moisture, and in the kitchen - resistance to stains and scratches. For utility rooms, such as laundry rooms, we usually choose the cheapest window sills.