What We Do

The Wood Window Alliance (WWA) was formed in 2007 by a group of manufacturers and suppliers to raise standards and promote the advantages of timber and aluminium-clad timber windows and doors. Today, we set the quality benchmark for industry performance, service life and sustainability.

We actively engage in independent research to substantiate our claims and work with partners to promote the use of timber in construction.


Advances in design and manufacture

Over the past two decades, the quality and engineering of timber windows and doors in the UK have undergone a revolution. Across our membership base there have been huge developments in technology leading to significant improvements in the performance of timber and aluminium-clad timber windows and doors. It’s our mission to let the market know of such developments to overcome outdated misconceptions that timber windows and doors made today still require laborious maintenance and provide lower levels of efficiency.

Advances in manufacturing has certainly played a strong role in extending the expected service – life of a timber window. Through choosing engineered timber and/or modified timber, investing in a micro-porous protective paint application with factory-finished glazing, our members make some of the highest quality and best value windows and doors on the market. To provide an idea of the manufacturing criteria which members have to meet, some key points are summarised below:

  • The type of wood can impact the window’s durability, natural hygroscopy (its ability to absorb and release moisture) and its resistance to destructive organisms including fungi. All window timber must meet durability Class 3 or better, or be treated with a water-based preservative to provide the same longevity. In general, WWA members use sustainably sourced engineered timber incorporating defect cut, laminated and finger-jointed timber, increasing stability and reducing knots and resin exudation.
  • Improved component design, using a slight slope – especially to the horizontal sections of the windows – to encourage water run-off to prevent standing rainwater, and water ingress into vulnerable areas.
  • Rounded edges (arrises), rather than sharp edges, to prevent the coatings thinning at these points thus maintaining durability.
  • End-grain sealants, to prevent water ingress into vulnerable areas around joints.
  • Timber treatment systems, to extend durability when required.
  • Opaque and translucent coatings applied in a controlled environment in the factory, providing better protection than brush applied finishes.
  • Improved drained and vented glazing systems, increasing glazing unit service life.


Promoting sustainability in design

We work in partnership with member bodies and organisations, including the Confederation of Timber Industries, the Timber Trade Federation and Wood For Good to promote the use of timber in construction. With the current consumer focus on reducing the amount of plastic used and the growing awareness of how materials used in a property can affect the well-being of those who live there, there has never been a better time to promote timber and aluminium-clad timber windows and doors.

Windows and doors made to our exacting standards are low carbon (the frames are carbon negative – they store more carbon than is produced manufacturing them). According to research by Heriot Watt University (Whole Life Analysis of timber, modified timber and aluminium-clad timber windows, 2013), every WWA wood window you install instead of a PVC-U window, saves approximately 160kgs CO2e over a 60-year service life. (That’s over 1.5 tonnes CO2e for the average house with 10 windows). Aluminium-clad and modified wood windows frames are also carbon-negative, saving approximately 140kgs CO2e over a 60-year service life when used instead of PVC-U windows.

Windows made to our standards get the top ratings in BRE’s Green Guide to Specification:

  •  All WWA-standard timber windows are rated A+
  •  WWA-standard aluminium-clad windows with a translucent coating on the wood frame are rated A+
  •  WWA-standard aluminium-clad windows with a solid colour coating on the wood frame are rated A