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Rationel Forma FormaPlus Triple Glazed Chop Sample

Forma & FormaPlus

Designed for a more traditional style of building, the Rationel FORMA window has an all-timber construction with slim, non-continuous bars. Featuring an ovolo moulded profile and angled glazing bead, FORMA is perfect for older, classic and country style houses. The aluminium external cladding also has a unique curved edge.
In terms of frame construction, the Rationel FORMAPLUS window is identical to FORMA. The only difference between them is the addition of external aluminium cladding included on the FORMAPLUS window. This inclusion ensures both minimum and easy maintenance characteristics.

  • Rationel Windows is a manufacturer with more than 60 years’ experience. Rationel employs 1,050 people in Denmark, England, Ireland and Poland, manufacturing premium-quality, durable and stylish windows and doors.

    Rationel Aura and AuraPlus Options

    Both Forma and FormaPlus have a wide variety of opening designs, glazing options and configurations. Along with the typical styles, Rationel FORMA and FORMAPLUS can be manufactured in bespoke shapes to correspond to an assortment of openings. Featuring fully adjustable and secure ironmongery (Secure by Design part Q compliant hardware), two gaskets and the option of trickle vents, FORMA and FORMAPLUS are carefully engineered with the customer in mind. Furthermore, all Rationel products prioritise energy efficiency. The slim design naturally takes advantage of the solar heat from daylight, and their exceptional insulating qualities reduce CO2 emissions significantly.
    Due to their energy efficient characteristics, both Rationel FORMA and FORMAPLUS are suitable for Passiv Haus buildings.
    Thanks to constantly enhancing efficiency and optimising their products, Rationel windows are designed to withstand all weather types, attempted break-ins, and the constant wear and tear of opening and closing windows year after year.

    Marine Suitability

    Rationel aluminium profiles are coated with a minimum of 60 microns thickness and are pre-anodized so can be called marine grade. The windows and doors will require regular maintenance as per the OE manual shown in the downloads tab of this page.

    Efficiency, Solidity, Dependability

    The Rationel product development is primarily based on the Danish market and climate which is predominantly coastal – similar to northern Scotland – so the products are suitable for coastal locations. We treat the aluminium for filiform corrosion prior to powder coating, and the products are also salt-spray tested at R&D stage. Furthermore, salt-spray batch testing is completed on all metal components, from cladding to hinges.

    “We basically offer a complete service. For over 60 years, our company has been based on excellent craftsmanship. This is still the case. At Rationel we take pride in delivering high quality,” Rationel CEO, Thomas Tvedergaard Larsen.

  • Typical LifespanFORMA: 60 years
    FORMAPLUS: 85 years
    Lead Time8-10 weeks from sign off
    Best U-Value0.78 W/m^2k
    Finishes Any RAL Colour
    for both timber and aluminium (FORMAPLUS only)
    GlazingDouble, Triple, Obscure, Solar, Laminated, Toughened
    Performance and
    Air Permeability: 600 PA
    Wind Resistance: 1600 PA
    Operation: 10,000 cycles
    Water Tightness: 600 PA
    Manufactured inPoland

  • Fixed Frame

    Fixed Frame Configuration

    Side Guided

    Side Guided Configuration

    Side Hung

    Side Hung Configuration

    Top Guided

    Top Guided Configuration

  • RAL Colour options in the standard range for Rationel products

    For a full list of colour options including clear laquer and granite textured colours (FormaPlus & AuraPlus only) please see page 7 of the Rationel Forma & FormaPlus Brochure.

    RAL 9010 – Pure White

    RAL 9001 – Cream

    RAL 7035 – Light Grey

    RAL 7015 – Slate Grey

    RAL 7016 – Anthracite Grey

    RAL 9005 – Jet Black

    RAL 7001 – Silver Grey

    RAL 8017 – Chocolate Brown

    RAL 6003 – Olive Green

    RAL 5013 – Cobalt Blue

    RAL 3011 – Brown Red

    RAL 7042 – Traffic Grey A

    RAL 7032 – Pebble Grey

    RAL 1001 – Beige

    RAL 7006 – Beige Grey

    RAL 1018 – Zinc Yellow

    RAL 6007 – Bottle Green

    RAL 5008 – Grey Blue

    Some colours are subject to additional lead time from Rationel.
    Colours shown should not be used in place of an official RAL colour sample. We cannot guarantee colour-accuracy when viewed on-screen or printed out.

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