Sometimes, the simplest ideas are absolute winners. Why should we install heavy stone window shelves and clad them with expensive metal capping when instead, we can just as well use rigid thermal insulation. Simply the best!
Before explaining how to do this let us remind you that stone window shelves create either new linear thermal bridges or deteriorate the effects of existing thermal bridges between the thermally more insulated facade and the thermally less insulated window frame. And we definitely do not want thermal bridges.
Usually, window shelves are made of water non-absorbent materials such as stone, plastics or metal. However, all these materials have high thermal conductivity and as they are placed on the facade below the window frame, the surrounding temperature is freely transferred into our indoor spaces.
Therefore, window shelves made of FIBRANxps are such a good solution. It is all about choosing the appropriate material with a smooth surface for easy further layering, like FIBRANxps ETICS or FABRIC. As the FABRIC panels are manufactured as long as 3 meters, they can be used without junctions and unnecessary fuss also on very wide windows.
The shelves are either installed during facade work, or openings are cut into the existing thermally insulating facade (ETICS). They are glued in place with a low expansion polyurethane adhesive, while its contacts with the facade are worked over with mesh and angle elements, making the junction watertight. A drip edge is fastened to the shelf’s outer edge. Finally, the shelf is either treated in the same way as the facade or we may just as well choose any other coating.
Should you decide to finalize your window shelves in the same way as your facade, we advise using a silicone final layer. This will enable the dirt to slide easily from your relatively rough shelves surface and with little effort your shelves will be self-cleaning. 🙂