Cortizo COR 70 Hoja Oculta is the architect's pick for minimalist projects. "Hoja Oculta" translates as "hidden sash". In this system the sash profile tucks away behind the frame, so from the outside all you see is a slim profile edge of just 66 mm. The effect is unique: fixed and opening sections look completely identical, delivering perfect symmetry and clean facade lines.
Here design and engineering work side by side. Shrinking the visible profile area enlarges the glazed surface, admitting 15-20% more daylight than standard windows. At the same time the system keeps every benefit of the 70 mm thermally broken platform: it offers excellent thermal insulation, holds back street noise and boasts high rigidity, making elegant panoramic structures possible.
Brand
Cortizo is the flagship of Spanish industry with headquarters in Galicia. The brand is famous for Cor Vision aluminum systems with virtually invisible profiles. If you need panoramic glazing for a villa or modern home — Cortizo is unrivaled.
More about CortizoTechnical Specifications
Design that hides itself. This inventive aluminium system uses a "concealed sash" so that only the frame shows from outside, blurring the line between fixed and opening panes while enlarging the glazed area.
Engineering Specifications:
Glazing Choices:
Largest Sizes and Finishes:
Tested Performance:
Documentation
Design that hides itself. This inventive aluminium system uses a "concealed sash" so that only the frame shows from outside, blurring the line between fixed and opening panes while enlarging the glazed area.
For a standard 2-sash tilt-and-turn window (1200 × 1400 mm) with basic double-glazed unit.
Alternative solutions from other manufacturers
Side by side
How Cortizo COR 70 Hoja Oculta stacks up against the closest matches from other brands.
| Specification | Cortizo COR 70 Hoja OcultaThis profile | Schüco AWS 75.SI+ | Kömmerling EuroFutur Elegance | Veka Softline 82 |
|---|---|---|---|---|
| Brand | Cortizo | Schüco | Kömmerling | VEKA |
| Material | Aluminium | Aluminium | PVC | PVC |
| Profile depth | 70 mm | 75mm | 70 mm | 82mm |
| Chambers | — | — | — | 7 chambers |
| Glass unit, max | up to 40 mm | up to 61mm | up to 39 mm | up to 52mm |
| Thermal (Uw) | ≤ 1.0 | 0.9 | ≤ 1.1 | 1.0 |
| Sound (Rw, dB) | ≈ 44 Rw(dB) | ≈48 Rw(dB) | ≈ 40 Rw(dB) | ≈47 Rw(dB) |
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FAQs
It is a 70 mm deep aluminium system built on prime-processed 6063 T5 alloy with a 1.9 mm profile wall gauge. The RPT thermal break uses 35 mm glass-fibre-reinforced polyamide bridges, giving a profile Uf from 1.7 W/m²K and a whole-window Uw down to 1.0 W/(m²·K). A triple-seal gasket arrangement secures Class 4 air tightness.
The concealed-sash geometry limits the glazing unit to up to 40 mm, accepting double or triple energy-efficient and tempered units. To reach the headline Uw of 1.0 W/m²K you pair it with a high-performance Ug=0.6 glazing unit. The hidden-sash channel simply leaves less room for the very thick panes that deeper systems can swallow.
Each sash is capped at 1300 mm wide, 2400 mm tall and 100 kg. For openings beyond those dimensions, or where you need glazing thicker than 40 mm, this is not the system to specify. Watertightness is rated Class E1200 and air tightness Class 4; no impact, wind-load or burglary-resistance class is published, so verify those separately.
Both share the 70 mm platform and 35 mm thermal break, so thermal performance is matched at Uw ≤ 1.0 W/(m²·K) and acoustics at ≈ 44 dB. The trade-offs are aesthetic versus capacity:
The opening sash tucks behind the outer frame line, so from the street only the frame is visible and fixed and opening panes blur into one. Just 66 mm of aluminium is on show, among the slimmest faces on the market. Indoors the window keeps a normal visible sash and handle and behaves like any standard unit.
Yes. By concealing the sash and exposing only a 66 mm frame face, the design enlarges the visible glazed area and lets in appreciably more daylight, an effect most noticeable on smaller openings. Finishes do not compromise this: any RAL colour, anodising, wood-effect sublimation, antibacterial coating and a Bicolour option are available.
