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Duratherm 400 Windows

Trusted - 10 Year Guarantee - Delivering Nationwide

Aluminium Window & Door Manufacturers Since 1985

UK Made • 10-Year Warranty • Nationwide Delivery • FastTrack Available

Low Lying Flat Roof

High Security Locking • Slim Sightlines • Enhanced Thermal Performance

COLOUR OPTIONS

DuraTherm 300 Aluminium Window Colours

Our DuraTherm 300 aluminium windows are available in standard white, the DUR colour range, textured paint finishes, a silver anodised finish and over 200 single or dual RAL colour finishes. Dual colour allows you to choose one colour internally and another externally, giving added design flexibility.

Standard White & DUR Colour Range

Standard White

Standard White

DUR 9010 Gloss
Black

Black

DUR 9005 Matt

Our aluminium windows are powder coated with a hardwearing polyester paint finish, baked onto the aluminium for a durable, low maintenance surface backed by a ten year guarantee.

Brown

Brown

DUR 8014 Matt
Cream

Cream

DUR 1015 Matt
Red

Red

DUR 3004 Matt
Blue

Blue

DUR 5011 Matt
Green

Green

DUR 6009 Matt
Dark Grey

Dark Grey

DUR 7016 Matt
Dark Brown

Dark Brown

DUR 8019 Matt
Silver Grey

Silver Grey

DUR 9006 Metallic

Please note that on-screen representations of painted colours are for guidance only and are intended to provide an indication of colour.

Duration Windows cannot be held responsible for any discrepancies between on-screen and actual painted colours.

Medium Grey

Medium Grey

DUR 9007 Metallic
White

White

DUR 9010 Matt

Textured Paint Colour Range

Basque Red

Basque Red

Antique Grey

Antique Grey

Steel Blue

Steel Blue

Our textured paint finishes offer a unique, cost effective way to add more character to your windows, with a subtly mottled surface that is ideal for both modern properties and restoration projects.

Here we have shown three examples from the wider range. For the full selection of available textured finishes, please follow the link below.

Full Textured Colour Range

RAL Colour Finishes

Pastel Green

Pastel Green

RAL 6019
Saffron Yellow

Saffron Yellow

RAL 1017
Water Blue

Water Blue

RAL 5021

DuraTherm 300 aluminium windows are available in any single or dual special RAL colour paint finish, with over two hundred colours available across the wider range.

This gives you the freedom to create a clean architectural look, match existing details, or choose different finishes internally and externally.

RAL Colour Chart

Examples of Popular Glass Options

Choose from clear, laminated, solar control and integral blind options to suit performance, privacy and comfort requirements.

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Frames and doors are supplied unglazed for safer transport and easier handling on site.
Supplied unglazed glass option
Supplied Un-glazed
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A simple and popular everyday glazing choice offering strength and clarity.
Standard clear toughened glass
Standard Clear Toughened
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Added security and safety performance with laminated inner construction.
Laminated security glass
Laminated Security Glass
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Low-emissivity clear glass designed to improve thermal efficiency.
Pilkington Activ Clear glass
Pilkingtons Activ™ Clear
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Neutral appearance glazing helping reduce solar gain while maintaining light transmission.
Pilkington Activ Neutral glass
Pilkingtons Activ™ Neutral
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Solar control glass with a more neutral finish for improved comfort in brighter elevations.
Sun-guard Super Neutral glass
Sun-guard Super Neutral
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High performance thermal glass option developed for improved insulation.
SGG Planitherm One glass
SGG Planitherm ONE
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Square leaded glass available in various thicknesses and finishes.
Leaded Glass
Square Leaded Glass
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Diamond Leaded glass available in various thicknesses and finishes.
Leaded Glass
Diamond Leaded Glass
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Horizontal Flat Astragal Bars
Horizontal Flat Astragal Bars
Horizontal Flat Astragal Bars
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Butted Flat Astragal Bars
Butted Flat Astragal Bars
Butted Flat Astragal Bars
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Flat Overlapped Astragal Bars
Flat Overlapped Astragal Bars
Flat Overlapped Astragal Bars
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Textured / Obscure Glass
Textured / Obscure Glass
Textured / Obscure Glass

Please note: These windows are delivered glazed for ease of transportation. They should be de-glazed prior to installation to allow for in situ Toe & Healing.

Multipoint Locking Handles

High-security shootbolt locking handles available in a range of finishes.

Standard Offset Espag Handles

Standard Offset Espag Handles

Simple, ergonomic and easy to use, these key lockable espag handles are of the highest quality and are built to last with an excellent finish.

Chelton® Espag Modern Handle

Chelton® Espag Modern Handle

Contemporary, slim and discreet. This handle provides an authentic looking window from the outside, keeping with a modern interior..

Friction Hinges

Options for standard use, egress compliance and restricted opening.

Standard friction hinge

Standard

Industry standard hinge. Holds the sash open using friction, allowing stable positioning without a peg stay.

Max opening angle: 50° – 80°
Egress easy clean friction hinge

Egress Easy Clean

Fire egress hinge option for windows over 450mm wide (Part B). Slides for easier external glass cleaning.

Max opening angle: 90°
Restrictor friction hinge

Restrictor

Provides a restricted opening for safety and ventilation, with the option to release for cleaning access.

Max opening angle: 37.5° – 50°

Note: Opening angles vary with window size. Ask for hinge details for your specific configuration.

DuraTherm 400 Technical

Technical information and specification guidance for the DuraTherm 400 aluminium window system, including sizes, performance, glazing and configuration options.

Performance

U-Value (Double Glazed)
1.4 W/m²K
Window Energy Rating
B Rating
Air Permeability
Class 4
Water Tightness
Class E / AE2400
Wind Resistance
Up to 2000+ Pa

Maximum Sizes

Side Hung
864mm (w) × 1400mm (h)
Top Hung
1400mm (w) × 1400mm (h)
Fixed Light
2100mm (w) × 2100mm (h)
Tilt & Turn
1200mm (w) × 2100mm (h)

System Overview

Frame Depth
70mm
Thermal Break
Polyamide
Glazing Thickness
24mm – 45mm
Glazing Options
Double / Triple Glazing

Configuration Options

Opening Styles
Side Hung / Top Hung / Fixed / Tilt & Turn
Styles Available
Casement / Flush / Slimline
Applications
Residential & Light Commercial
Suitability
New Build & Refurbishment

Security

Locking System
Multi-point Locking
Accreditation
PAS 24 Compliant
Glazing Options
Internally Beaded
Hardware
High Security Locking Options

Compliance & Features

Building Regulations
Part L Compliant
Thermal Efficiency
Enhanced Insulation Performance
Weather Performance
Excellent Air & Water Resistance
Finish Options
200+ RAL Colours Available

Product Literature

Download specification sheets and full product brochures.

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