Traditional style
Designed to complement traditional British architecture, look no further than FORMA and FORMAPLUS. Beautifully styled, these designs bring the classic into the current day to create a finished look that’s simply transformational. It’s sheer sophistication, reimagined.
Both options work to bring a softer line to your windows, helping your project to blend more seamlessly into its surroundings. Available with or without glazing bars which particularly suits this style of windows.
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Classic profile on the inside
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Classic style glazing bars
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Classic angled glazing bead
Timber*
Our timber windows consist of solid wood from the very innermost structure through to the external, resulting in excellent thermal and acoustic performance, combined with easy maintenance. It is available in either double or triple glazing, and has been designed to exhibit the very best in energy efficiency.
Rationel FORMA is a timber product.
*Illustration of material only – this colour combination can not be purchased.
Aluminium clad timber
Rationel FORMAPLUS is an aluminium clad timber product.
Rationel FORMA
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Triple glazed
– Best performance: 0.78 W/m2 K U-value
– 42 dB Rw sound reduction
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Double glazed
– 40 dB Rw sound reduction
Key features
– Timber frame
– Minimum 40-year life expectancy
– Over 200 colours available
Rationel FORMAPLUS
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Triple glazed
– 42 dB Rw sound reduction
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Double glazed
– 40 dB Rw sound reduction
Key features
Aluminium-clad timber frame
– Low-maintenance
– Minimum 40-year life expectancy
– Over 200 colours available, with no extra charge for dual colour*
*When choosing from our standard colour range
Colours
*When choosing from our standard colour range
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RAL 9010
Pure white
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RAL 9001
Creme
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RAL 9003
Signal white
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RAL 9002
Grey white
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RAL 7035
Light grey
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RAL 7044
Silk grey
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RAL 7038
Agate grey
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RAL 9007
Grey aluminium
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RAL 7030
Stone grey
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RAL 7037
Dusty grey
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RAL 7001
Silver grey
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RAL 7015
Slate grey
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RAL 7012
Bastalt grey
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RAL 7016
Anthracite grey
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RAL 7013
Brown grey
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RAL 1035
Pearl beige
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RAL 7032
Pebble grey
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RAL 7006
Beige grey
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RAL 7022
Umbra grey
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RAL 6003
Olive green
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RAL 6009
Fir green
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RAL 8017
Chocolate
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RAL 8019
Grey brown
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RAL 7024
Graphire grey
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RAL 9004
Signal black
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RAL 7021
Black grey
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RAL 8022
Black brown
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RAL 9005
Jet black
Granite colours (aluminium clad timber only)
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G01 White
(SAA10F)
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G10 light grey
(S2150)
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G20 Medium grey
(S2400)
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G30 Warm grey
(S2900)
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G60 Dark grey
(S2100)
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G80 Black
(S900)
Obscure panes
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Satin
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Cotswold
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Listral D
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Silvit
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Crepi
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