With cast-in-situ driven piles and bored piles the pipe systems are attached to the insides of the reinforcing cages before they are installed. The flow and return lines in the area of the pile head are fitted with a pressure gauge and ball valve. The absorber units are pressurized at a pressure of 6 bar which is maintained during the installation and concreting operations. The pipe ends with pressure gauge and ball valve can be protected by means of a PVC overtube to prevent damage during the construction work. Particular care needs to be taken during the concreting operations to ensure that the steel feed pipe for the concrete does not damage the pipe circuits when it is inserted into the reinforcing cage in the bore. In the case of augered piles, the absorber units fixed to the reinforcing cages can be pressed or vibrated into position with the reinforcements. The pipes must be properly fastened and the bottom loops must be secured using a welded ring. In the case of mixed-in place piles which are equipped with a reinforcing cage, the absorber units can be integrated by means of the reinforcing cage, as with augered piles. These piles are rigged with HDPE piping in the factory and the pipe circuits are attached to the inside of the reinforcing cages. To allow the absorber units to be joined up to the manifold/header blocks via the connecting lines, polystyrene packing is placed in the area of the pile head. This is removed after the pile driving operation. These openings provide access to the pipes which can then be joined to the connecting lines by means of thermofusion connectors. In the case of steel-reinforced concrete hollow piles and micro-piles, two pipe loops (4 pipes) can be threaded prior to pouring and compressing the concrete, similar to bore hole heat exchangers. However, a minimum inside diameter of 120 mm is a must. All types of piled wall are suitable for geothermal applications. For this purpose, the pile must have a reinforcing cage. As a rule, the piles are rigged at suitable distances to ensure that mutual interference does not reduce performance. Mixed-in-place walls must be equipped with reinforcing cages. In the area of the embedded depth of the wall, both sides can be utilised, whereas only the ground-facing side of sub-level walls is suitable. If the piled wall is to be fitted with anchors their positions must be coordinated with those of the pipe installations. Only diaphragm walls constructed with the two-stage method can be used for geothermal applications as only these have reinforcing cages. The spacing for the pipe installations is between 15 cm and 50 cm. In the area of the embedded depth of the wall, both sides can be utilised, whereas only the ground-facing side of sub-level walls is suitable. The positions of wall anchors must be coordinated with those of the pipe installations. The pipe installations are installed and protected in the same way as in the case of piles. As a rule, the pipe systems are laid in the subbase beneath the foundation with spacing of 20 cm to 40 cm. Suitability for geothermal applications will have to be examined precisely as capacity will be heavily influenced by whether or not insulation is incorporated.