Zyle Fenster
EcoTherm SL Flush Casement
An aluminium-clad timber flush-casement window combining a level external face with modern double- or triple-glazed performance.
What this system is designed to do
An aluminium-clad timber flush-casement window combining a level external face with modern double- or triple-glazed performance.
Where we would specify it
It suits contemporary or traditional projects needing flush sightlines, low external maintenance and the warmth of timber internally.
Features and performance
- Flush external sash and frame relationship
- Engineered timber core with aluminium weather protection
- Double- and triple-glazed versions
- Internally glazed construction
- Full RAL external colour range
- Factory-applied internal timber finish
Technical specifications
Colours and finishes
Colours and finishes
Any RAL colour, outside and in.
Powder-coated aluminium protects the outside, and the engineered timber inside is finished in paint or stain. White, RAL 9016, is standard, and any RAL Classic colour can be specified.
Outside
- Material
- Aluminium cladding
- Finish
- Polyester powder coat
- Colour
- White (RAL 9016) as standard, or any RAL Classic colour
Inside
- Timber
- Engineered redwood as standard; engineered hardwood, Accoya or European oak
- Finish
- Three-coat factory spray: water-based Teknos microporous paint or stain
- Colour
- White (RAL 9016) as standard, any RAL Classic colour, or a stain from the TRC range
Standard colours 29
White, RAL 9016, is standard. Select colours to add them to your project enquiry.
RAL 1035 Pearl beige and RAL 9007 Grey aluminium are effect finishes, made for a powder-coated aluminium face rather than painted timber.
Any RAL Classic colour
On the aluminium, the timber or both.
Also available
- Wood stains The timber inside can be stained rather than painted, from the TRC stain range.
- Glazing beads Externally beaded. Supplied in white, grey or black.
- Spacer bars White warm edge spacers as standard; silver or black optional.
Your selection
Colours on screen are a guide only, and pearl and metallic finishes cannot be shown. Add your choices to your project enquiry and we will go through them with you.
Add to project enquirySource: Zyle Fenster’s specification and FAQs for this system. Standard colour range and glazing bead colours: Zyle Fenster, September 2026.
FAQs
Common questions, answered.
The essentials on the EcoTherm SL Flush Casement: what it is, how it performs, the options, and where it fits best.
Still have a question?
Our team can talk you through the detail for your project.
What is EcoTherm SL Flush Casement?
An aluminium-clad timber flush-casement window combining a level external face with modern double- or triple-glazed performance.
How does EcoTherm SL Flush Casement perform?
Published whole-window Uw values are 1.2 W/m²K for EcoTherm double glazing and 0.8 W/m²K for EcoTherm+ triple glazing. PAS 24 enhanced-security compliance is standard.
Which design and specification options are available?
EcoTherm uses a 28 mm double-glazed unit; EcoTherm+ uses a 48 mm triple-glazed unit. The aluminium exterior is available across the RAL range with a factory-finished timber interior.
When would Eco Home Windows specify this system?
It suits contemporary or traditional projects needing flush sightlines, low external maintenance and the warmth of timber internally.
Downloads
Drawings and technical data.
13 files for this system, published by Zyle Fenster. Tell us who you are once and everything here opens for the rest of your visit.
Datasheets 2
Specification sheets and technical data
CAD drawings 1
DWG section details for drawing packages
Revit families 5
Parametric families for Revit models
IFC models 5
Open BIM geometry for any IFC-capable tool
Before you download
Who should we send this to?
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