The present invention refers to a building system for internal insulating counter-walls of buildings, composed of prefabricated panels containing a thermo-reflecting multi-layer thin insulating layer.

The need of making integrative interventions on existing buildings to obtain an improvement of the thermal insulation performances, in terms of protection of the internal living space both in winter, from the cold, and in summer, from heat, has become a priority and is often required by legal standards in force. The increase of the efficiency of the building envelope determines a high reduction of the energy demand for air conditioning, and an improvement of the comfort.

Many techniques and materials are known, to increase the insulating capabilities of the external wall of existing buildings. Such possibilities can be classified into three categories: 1) placing an insulating material outside the existing wall (external coat) ; 2) placing an insulating material in the interstitial recesses of the existing wall; 3) placing an insulating material inside the existing wall (internal coat) . The third, above-described category, the "internal coat", is in many cases the only feasible one (for example when the architectural features of existing facades must not be altered, when one operates only on portions of the building, etc.) .

When an "internal coat" is made, the physical space occupied by the new insulating material decreases the working space of preexisting rooms. For this reason, the relationship between the insulating power of the "internal coat" and its thickness is fundamentally important.

Between the thermal insulating materials used in buildings, thermo-reflecting multi-layer thin insulating materials are also included. The insulating power of such materials is very high. However, its textile nature makes its installation very complex, needing a very accurate positioning adapted to create interstitial air chambers of accurate contour sizes.

This difficulty in installation and the consequent cost increase actually limits a widespread use of these particular thermal insulating materials, which have the best ratio between overall sizes and performances among insulating materials known in buildings .

Object of the present invention is solving the above problem of a difficult correct installation of thermos-reflecting thin insulating materials, providing a building system for internal insulating counter-walls of buildings composed of industrially pre- fabricated panels, of a small thickness and high performances, and an easy installation. The further advantage is having available a wholly correct positioning of the insulating layer, which is placed between air chambers having a constant thickness and lacking irregular compression points, which would limit its efficiency (typical irregularities of conventional installation systems) .

The above and other objects and advantages of the invention, as will result from the following description, are obtained with a building system as claimed in Claim 1. Preferred embodiments and variations of the present invention are the subject matter of the dependent claims.

It is intended that the enclosed claims are an integral part of the present description.

The present invention will be better described by some preferred embodiments thereof, provided as a non-limiting example, with reference to the enclosed drawings, in which:

- Figure 1 is an exploded perspective view of a first preferred embodiment of the building system of the invention;

- Figure 1A is a side sectional view of the detail of one of the panels of the building system of the invention;

- Figure 2 is an assembled side sectional view of the building system of Figure 1;

- Figure 3 is an exploded perspective view of a second preferred embodiment of the building system of the invention; and

- Figure 4 is an assembled side sectional view of the building system of Figure 3.

With reference to the Figures, a preferred embodiment of the building system of the present invention is shown and described.

It will be immediately obvious that numerous variations and modifications (for example related to shape, sizes, arrangements, materials and parts with equivalent functionality) can be made to what is described, without departing from the scope of the present invention, as described in the enclosed claims.

The designed solution deals with a building system of panels for making internal insulating counter-walls, adapted to improve the energy performances of external walls of buildings with any use destination.

The objective is making panels with high thermal insulation, having a small thickness (anyway lower than that of existing panels with the same performances) , with an easy installation. Strong advantages in terms of performances, economy and ecology are obtained.

High insulation and small thickness generate a high energy efficiency of the building envelope with optimum living comfort, associated with a limited reduction of the useful space of preexisting rooms .

Such panels are conceived to be used in energy re- qualification of existing buildings, but can found application also in new constructions.

The requirements of high insulating performances and small thickness are satisfied through the correct positioning from the physical-technical point of view of a thermo-reflecting thin insulating mattress, inside an industrially pre-fabricated composite rigid panel, adapted to be quickly and easily installed in adherence or next to an existing wall of a building.

With reference to Figures 1, 1A and 2, herein below the main components are synthetically described, with their features, for making a building system P of the invention for internal insulating counter-walls of buildings, according to a first preferred, but not limiting, embodiment, composed of a composite multi-layer panel, which comprises:

• at least one first buffer panel 1, composed of a rigid slab made of fiber cement or plaster fiber or recycled wood or other material, with variable thickness;

• at least one first macro-porous, spacer panel 2 of the honeycomb type or other geometry, composed of a honeycomb panel made of cardboard or wood or other material, whose thickness is included between 10 and 20 mm; the first spacer panel 2 is made integral with the buffer panel 1 through gluing;

• at least one thermo-reflecting multi-layer thin insulating layer 3, preferably composed of multiple layers of which: two metal - coated coating films 3a, 3b with reinforcing grid 3c, layers of foam 3d alternated with reflecting films 3e, layers of natural insulating material 3f (lambs-wool or the like) , all suitably assembled through thermal gluing or wire stitching;

• at least one second macro-porous spacer panel 4, composed of a honeycomb panel or other geometry made of cardboard or wood or other material, whose thickness is included between 10 and 20 mm; the second spacer panel 4 is made integral with a second buffer panel 5 through gluing;

• at least one second buffer panel 5, composed of a rigid slab made of fiber cement or plaster fiber or recycled wood or other material, with variable thickness;

• at least one supporting structure 6 placed on a perimeter of the panel, with possible intermediate cross-members 6a, composed of a framework in wooden listels or in synthetic foam or in other materials with a suitable mechanical strength - with thickness useful to create an interstitial space with optimum size depending on the thickness of the insulating layer (the thermo-reflecting multi-layer thin insulating mattress, being capable of being compressed, has an optimum insulating power when it is freely arranged at a certain known thickness) .

Figures 3 and 4 show the building system of the invention in a second embodiment thereof, different from the first due to the presence of only one between the first and the second spacer panel 2 and 4. The insulating layer 3 is therefore in contact with the second buffer panel 5.

As regards the technical features of the building system P of the invention, the composite counter-wall panel described so far allows obtaining a small value of final thermal transmittance , above all due to the integration of the thermo-reflecting layer inside the panel itself. The thermo-reflecting material has very small thicknesses, low values of thermal conductivity and is characterized by its reflecting and low emissive operation. These latter ones are major aspects, which allow increasing the energy performances of the whole system, both during winter, and during summer, and ensure its application in the different climatic areas and the reduction of the energy demand for heating and for cooling.

Moreover, in the described system:

- the global stratigraphy of the panel has high thermal hygrometric characteristics without interstitial or surface condensate phenomena;

- the high mechanical resistance of the composite structure confers to the panel optimum strength characteristics as compared with its own weight, much bigger than those for known panels for counter-walls;

- the panel can be pre-fabricated industrially, allowing the optimum placement of the thermo-reflecting multi-layer thin insulating layer (which determines its optimum performances) , which cannot be obtained with an artisan in a yard; due to its small weight and thickness, its planarity, it can be easily stored, transported, moved (even manually) , and quickly assembled, needing only the on-site installation of its surface finishing.