Design 5


  • Traditional timber construction with aluminium cladding sections.
  • Designed to accommodate PN Combi hinge system.
  • 6mm gap between sash and frame maintained with any sash type.
  • Aluminium corners and transom/mullions mechanically connected.
  • Concealed drainage
  • All areas can be externally or internally glazed.
  • Timber section designs can be tailored to aesthetic ‘taste’.
  • Multi-point espagnolette locking.
  • Security tested to BS7950.
  • High performance weather tested.
  • Excellent thermal performance.
  • High acoustic performance - dependant on glass specification.


A timber / aluminium composite window system

The Design-5 timber / aluminium composite window system is available in the following range of styles:
• Projecting Side Hung
• Side Swing Fully Reversible
• Projecting Top Hung
• Top Swing Fully Reversible
• Internal or external fixed glazed areas

Internal timber
The timber sections of the window are jointed with traditional mortise and tenons. FSC® accredited Pine is offered and some hardwoods may also be specified.

Timber finish
Double vacuum preservative treated providing a 30 year guarantee against insect attack and fungal decay. The timber is then fully factory finished with either a translucent stain or opaque paint

External Aluminium
Aluminium extruded from alloy EN AW-6063 T6 in accordance with BS EN-755. Polyester powder coated to BS 6496-1984 with full RAL and BS range available or anodised to BS 3987.

Furniture and fittings
The Design-5 window can accommodate the full range of Peder Nielsen Combi-500 hardware which offers a wide choice of opening options. Various locking options are also available which include enhanced security to Secured by Design.

Secured by Design
Security tested to BS 7950.
Trickle vebtilation
A wide variety of through-frame, through-sash or glazed in trickle ventilation options are available.

The window has been tested using a range of standard industry seals. In addition to the compression seal, an 11.5 woolpile with fin is used around the sash and a security tape is incorporated to secure the glazing.

The current 'off the shelf' option for the sash and for externally glazed fixed areas is 28mm. Internally beaded or triple glazed windows are also available

WWeather tightness test BS 6375: Part 1: 2004 undertaken at the BRE dated 08 May 2006, test report number 229 098:-
• Air permeability: 600pa Class 4
• Water tightness: 1050pa Class E1050
• Resistance to wind load: 3000pa Class C5
Full test report available upon request.

The window is certified to BS 7950 and Benlowe are a Secured by Design license holder.


Awaiting independent certification for both Thermal & Energy Efficiency rating. Conforms to Document L and J and initial tests indicate an overall window U-value of 1.5 on the standard design with 28mm units and a window U-value performance of 1.0 with Design 5+ using 44mm triple glazed units.

Ancillary profiles
Various cill options, frame extenders and coupling arrangements are available. For assistance on glass options or performance requirements please contact our technical team.

Vertical Section


Projecting Top Hung Sash / External Beaded Fixed Light

Tow Swing Reversible Sash / Internally Beaded Fixed Light


5 Year Guarantee against the need to totally repaint factory finished stained joinery as defined in BS EN927-1.

10 Year Guarantee against the need to totally repaint opaque factory finished joinery as defined in BS EN927-1.

10 Year Guarantee on all factory fitted double glazed units.

30 Year Guarantee on timber components against insect attack and fungal decay.

25 Years Guarantee on aluminium cladding

In Association with

Call our DESIGN TEAM on 0116 239 5353 to discuss your requirements.