The window sills, also called “trays” can be made of different materials and shapes.
The cheapest are made of marble, with a rectangular section and a maximum thickness of 3 inches. The most expensive can be realized both in marble and granite have a contoured exterior profile. In the middle are the concrete sills. These can be a great alternative for when architectural requirements should be given a particular shape to the exterior.
Being that the concrete artifact was created to “die casting”, ie in the form of liquid contained in the mold, once established as the most done. Typically concrete sills are a little more expensive than a simple plate of marble national, but become immediately convenient when there is the need of a decoration on the outer profile. The decorations on the exterior concrete benches are the “insignia”, these can be given any shape, their implementation is usually by means of molds in polystyrene.
As you can see from the pictures, the shape and color of the concrete sills is subject to the type of property. The pallets in cement can be manufactured in two types of concrete: the one with the white cement allows to obtain light shades, from salmon pink to “blue”, those in gray cement are indicated for the tones from gray to dark brown precisely. The finishes of the visible parts usually relate to the flat part of the sill, that is where the lean arms. Here you can choose between keeping the smooth finish “bottom mold” of the building concrete or decide to further smooth the floor, going to discover the aggregate that makes up the concrete.