Sandwich exterior walls is a multi-layer structure consisting of reinforced concrete on internal and external layer and a layer of thermal insulation between them. The layers are joined together by diagonal connections of stainless steel which intersect the thermal insulation layer. The connections also transfer the weight of the external leaf to the internal leaf, meaning that the external leaf is a suspended construction element and suspending other constructions from the external leaf is generally not allowed.
Sandwich facades can be divided into three groups based on the structure of the building:
- self-bearing non-stiffening walls
- load-bearing stiffening walls
- non-load-bearing stiffening walls
The external leaf of sandwich facades is usually 80 mm thick (except for panels finished with quarry tiles; in the case of tiles that are 15 mm thick, the external leaf is 95 thick), the internal leaf is 80…180 mm thick and the thermal insulation layer is generally 100-250 mm thick due to requirements of the wall structure and costumer´s wish. The thermal conductivity or U-number of such walls is, for example, in the range U = 0.38…0.16 W / (m2K) when using glass wool insulation with ventilation grooves. When choosing the thickness of the layers of SW exterior wall panels, we recommend consulting E-Betoonelement specialists.
In the absence of special conditions, stone wool, expanded polystyrene or polyurethane boards can also be used as thermal insulation material.
In order to avoid cracks in the external leaf resulting from decreasing volume, changes in temperature and other external forces, elements longer than 6 m should be avoided, or the external leaf of longer elements should be divided into smaller segments by dummy joints in order to direct possible cracks.
The following table shows the technical features of the bearing SW-exterior wall panel as an example:
Layer thicknesses - internal layer 150 mm, glass wool insulation 200 mm, outer layer 70 mm.
Check out the finishing options for SW outer wall panels here.
Elemental dimensions are selected according to the architecture and design of the building, taking into account the technological capabilities of the factories. Using modern production lines and plant installations, it is possible to produce very large assembled wall elements.
- Length 12,000 mm
- Height 4 100 mm
- Weight 32 t
The use of large and vast elements requires the use of special transport and special cranes. When using large-scale elements, we recommend that you consult with our specialists in advance.