Science and design: surface modification for timber window frames

The aim of this project is to promote timber as the sustainable material of choice for outdoor use in the window construction industry through a unique combination of interlinked investigations: 1. A new product development process for timber window frames; 2. Scientific advancement of surface modification technology; 3. Replacement of non-sustainable materials. This research is an investigation utilising material and product development for the timber construction industry, promoting scientific advances in surface engineered timber. The scientific method of modifying the surface of timber consists of a spray application of water-based graft chemicals that remove natural extractives, chemically bonding molecular chains to increase the surface potential for an adhesion bond. This method of modification is done: ▪ to increase the tensile strength of an adhesion bond; ▪ to promote the durability of paint on a timber surface. Results of adhesion bonding tests demonstrate, on average, a four-fold increase in tensile strength compared to unmodified samples, with two species achieving an overall increase, 10-fold that of an unmodified sample of the same species. The success of this practical testing is applied in the development of a timber window frame that will utilise this new technology to create an environmentally friendly product outcome. Surface-engineered sustainably produced regrowth timber is used and is comparable, and in some cases better, than unsustainable hardwoods which currently dominate the timber window frame market. The next step is engineering timber to advance past its current state, improving characteristics to compete with aluminium and unplasticised polyvinyl chloride (uPVC), which are popular materials in the manufacture of window frames and are toxic burdens for our environment. The importance of ensuring engineered plantation timber is at the same quality of unsustainable hardwoods, uPVC and aluminium, is paramount in guaranteeing an improved, sustainable future.