Examination of the state of the existent support
The plaster layer is fundamental to obtain the perfect flatness of the substrate. This requisite is ideal to install correctly a system which envisages the use of a very reduced-thickness insulation. Noteworthy is that it is necessary to prepare a cohesive and dust-free base: this is what allows the perfect adhesion of the adhesive. In case of necessity, it is appropriate to proceed with the drafting of a surface fixating primer.
The application of the adhesive must be realised on the back of the panel (the part with the rigid crust is the one that has to remain extern and receive the successive finishing shaving). Use a toothed spatula (teeth of 6-8 mm) applying the appropriate pression, lay evenly the adhesive on the entire surface of the panel.
The adhesive must not penetrate the joints, but in case they form themselves, these must always be filled with the same insulating material to prevent the formation of thermal bridges and possible cracks.
Between the insulating panel and the support there must not circulate air, hence the insulating panel must be fixed to the support in an even way applying the adhesive on the entire surface of the panel itself. To guarantee a better adhesion, it is possible to apply a layer of adhesive on the support too (use the same toothed spatula).
Afterwards, apply the panel to the support being careful to properly make every area adhere (if necessary, proceed with the superficial beating of the panel with a plastic plastering trowel); verify the perfect adhesion and flatness with the use of an aluminium straight edge.
The insulating sheets must be mechanically fastened using plugs. The plugging diagram and number of plugs varies according to the type of wall, but always respecting at least 6 plugs per square metre. The choice of the correct plug will depend on the length and type of the substrate.
The length of the plugs will depend on the anchor depth, on the thickness of the old plaster, on the thickness of the glue and on the thickness of the insulating material. The plugs must be installed after the hardening of the adhesive, taking care of maintaining a minimal distance of 15 cm to the corners of the panel. Use exclusively plugs of type DIPK Fischer or similar.