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Profles for thermal break windows

This series is the evolution of 77IW, created in order to meet the demands of a minimalist modern market.
Sash is hidden by the frame, allowing for the reduction of the visual impact of aluminum and the increase of the brightness of the interior.

These systems have high thermal insulation, which is obtained through the use of polyamide alveolar bars of 39 mm and reinforced by the insertion of special insulating strips. The solution allows for the reduction of convective motions inside the cavity of the profiles and gives performance values thermal acoustic certificates of considerable value.
It is characterized by sectional profiles from 77mm frame to 87 mm sashes and provides customers with the most demanding solutions and better performance in the AluK range.

77IS series for hidden casement windows has the same frame depth, thermal break and tightness of 77IW, keeping the top-quality performance on windows with a clear and “minimalist” shape.
The jamb section is 77 mm deep and 79 mm high, while the wing is 81 mm. The wing is 6 mm back from the jamb outside and 10 mm overlapping inside.
This series allows to assemble windows with single and multiple wing, side-hung and, turn-and-tilt, with fixed fanlights, screens and shop-windows.
Same sections can also be used as openable parts of curtain walls such as ALUK SL50 and SL60 systems.
The final product will have to respect the provisions of EU Construction Products Directive (89/106/EEC), with CE-marking apposed, as attestation of conformity according to the relevant clauses of EN 14351-1 “Windows and doors – Product Standard, performance characteristics. Part 1 Windows and external pedestrian doorsets without resistance to fire and/or smoke leakage
The Manufacturer is obliged to respect, for the relevant clauses indicated in Annex ZA of this standard , the mandated levels or classes in the place of use, if applicable.


The extruded aluminum sections are made from homogenized billets, EN AW-6060 alloy (Chemical composition according to EN 573-3 and mechanical properties according to EN 755-2 standard), with limited composition tolerances, suitable for anodizing or painting.
All extruded aluminum sections are supplied at physical state T6; dimension tolerances are in compliance with EN 12020-2.
The thermal break is obtained by inserting some special small reinforced polyamide bars, mechanically hooked to aluminum knurled extruded sections.
A high mechanical stability of sections and thermal insulation are guaranteed by honeycomb insulating bars 39 mm thick.
The thermal transmittance of frames Uf, calculated according to EN ISO 10077-2, is included between 0,9 and 1,6 W/m2·K.
Gaskets, either static or dynamic, are made of EPDM (ethylene + propylene elastomer). Central gasket is placed in a retracted position in order to create a large pressure equalisation chamber.
The particular shape reduce at the highest level convection between jamb and wing.
Patented ALUK accessories of the highest quality are expressly designed by ALUK itself to grant the utmost reliability and safety.
Corner joints allow the assembling by riveting, caulking or screw. Hinges, made from aluminum extrusion too, are equipped with bushes made of anti-friction and synthetic material with stainless steel pins and screws.
The system allows the application of glazing with thickness from 30 to 40 mm on single or double insulating units or panels. In order to choose the right type of glass, of blockings, of sealing and in order to assemble it properly, the fitter shall scrupulously comply with glazing manufacturers specifications and instructions. aluminum glazing beads and inner and outer EPDM gaskets fix glass panes.


The anodizing process starts with a mechanical pre-treatment consisting in a scotch-brite brushing of raw profiles. Afterwards, all the other electro-chemical treatments and relevant controls are performed in compliance with Technical Directives of European quality mark QUALANOD.
The anodic oxide layer thickness is checked in compliance with international standard EN ISO 2360 (eddy current method), while the fixing quality of the anodic oxide layer is referred to ISO 3210 and EN 12373-4 standards.
Treatments are guaranteed by the quality mark (EURAS-AWAA) QUALANOD, and a certified Company UNI EN ISO 9001:2000 carries them out.
Sections with visible parts have the “Spazzolato E2” finishing (brushed), while hidden sections have the “Satinata Chimica E6” finishing (chemically glazed).
The minimum compulsory oxide layer thickness is 15 microns for external architectural use, can be increased to major classes (20 or 25 microns), according to customer’s requirements and/or national laws in the place of destination. Possible anodizing treatments are: natural silver, light bronze, medium bronze, medium bronze electro-colored, dark bronze electro-colored, black electro-colored.
Painting is done with powders and color can be chosen from the RAL gamut of colors, from our color quire and/or based on customer’s requirement.
Before painting, section surface is pre-treated with a “in-tunnel” treatment, i.e. :
• degreasing
• washing
• etching
• washing
• chromium plating
• double washing in demineralized water
• furnace drying process
After that, special powders are applied by spray painting with electrostatic alternate spray guns, into an automatic booth, then dried into furnace for paint polymerization.
The powders used are QUALICOAT homologated and a certified Company UNI EN ISO 9001:2000 carries out painting.
The minimum compulsory paint layer thickness shall be at least 60 micron for external architectural use. The whole sections painting cycle is carried in full compliance of quality standard QUALICOAT.

Depth of outer Frames 77 mm
Depth of sash 81 mm
Application windows. 1 door, Turn&tilt, taped, overlight, Vasistas.

Minimum depth: 30 mm Maximum: 40 mm

Type: panel, double glass, triple glass

Turn and tilt [kg] 130 [Kg]
Thermal Transmittance

Obtained by calculation according to the international standard:

UNI EN ISO 10077-2

Uf= 0,9 - 1,6 W/m2K

Thermal transmittance (triple glazing)

Window frame 1.530 mm x 1.480 mm

Ψ Window frame 0,05 W/mK

Ug Window frame 0,5 W/m2K

Uw=0,90 W/m2K
Type of seal open joint
basic performance -----> high performance

Air Permeability


EN 12207

1 2 3 4            

Water Permeability

EN 12208 (configuration as full out exposed)

1A 2A 3A 4A 5A 6A 7A 8A 9A E1350

Wind resistance

test pressure EN 12210

1 2 3 4 5