Timber doors and windows deserve a bigger share of the Australian market.
Few things set the tone of a building more than its windows and doors. And for the timber industry, they represent an opportunity to improve a once-dominant market that has been eroded by aluminium and steel.
Consumer concerns regarding fire safety, maintenance and price have driven much of the move away from timber. But these are usually misplaced, especially when price is calculated with respect to the comparative energy efficiency of each product type and the flow on insulation capability and ongoing heating costs of the overall building.
Tracey Gramlick, Executive Director and CEO of the Australian Window Association (AWA), says, “Timber windows are an extremely energy efficient product given their wonderful innate thermal properties. They meet the mandatory energy efficiency requirements quite easily.”
The great advantage of timber is its adaptability. Timber products look just as at home in seamless modernism as they do in 19th century restorations. Skilled manufacturers can deliver an almost infinite variety of profiles and shapes at low cost using today’s revolutionary machinery and technology, and, for the consumer, a new look for their streetscape is as simple as a trip to the paint shop.
It’s hardly surprising to see timber windows and doors taking a starring role in the pages of glossy design magazines, but there is scope to expand in all sectors of the market where mainstream builders and designers are sometimes accepting what their clients see as an ‘easier’ product in place of timber options.
Education from within the industry is the answer. As Gramlick says, “Most innovative timber window companies work with architects and building designers to offer solutions in using timber, especially in heritage work, bushfire zones and energy efficiency.”
Armed with the knowledge of timber’s adaptability, efficiency and strength, more designers and builders feel confident advocating for the product with clients, and the superior result speaks for itself.
Hitting the mark
There are multiple Australian standards for windows and doors, and some of these form the basis of misplaced concerns with specifying timber product.
One is understandably worrying: AS 3959-2009 Construction of buildings in bushfire-prone areas. However, as both the AWA and the other main industry body, Window and Door Industry Council (WADIC), have shown, timber options include those deemed acceptable to withstand exposure up to a BAL–29 condition (Bushfire Attack Level 29, including ember attack and a heat flux up to 29kW/m2).
Bushfire-resisting timbers include silvertop ash, blackbutt, red river gum, spotted gum, red ironbark and kwila (merbau), and other dense species meet many of the standard’s requirements for homes in lower BAL areas.
Both AWA and WADIC have produced comprehensive literature regarding windows and doors in bushfire prone areas. You can download their publications at awa.org.au/documents/item/174 and wadic.org.au/bushfire_compliance/bushfire_guide_2012.pdf.
One point of emphasis is that the material specification doesn’t exist in isolation, but as part of a broader location- and structure-based analysis and as part of a total fire risk strategy that can incorporate risk-lowering structures, including styles of doors and windows and shutters.
Gramlick adds that “Fire retardant coatings and intumescent fire-resistant paints are available for frames.”
The AWA’s research backs up their confidence in the product. As Gramlick says, “Bushfire resistant timber window system tests are now frequently done to include frames, glass and seals.”
Lasting protections
Concerns regarding resistance to rot and ability to weather well are also common for timber doors and windows. The industry itself has had some fault here, occasionally buying down to a price point using materials that are not up to the durability requirements of components that will be exposed to the worst of the challenging Australian weather.
While this has largely been driven by consumer demand for cheaper product, it has in some cases undermined confidence in the material. Coupled with this is the ability of good coatings to cover up a multitude of sins in early years, only to reveal problems later as joints distort and the coating cracks, removing its protection.
As Douglas Curr, Technical Sales and Specification Manager from Intergrain and Teknos, an industrial wood coatings specialist, says, “The key to the lifespan and performance of timber joinery is in maintaining the dimensional stability of the timber. Uncoated or inadequately protected doors and windows will expand and contract as atmospheric conditions change, so joints will open, doors and windows will swell, and sometimes seize.”
Using quality Class 1 durable timbers is the best starting point for a reliable product, but should be part of a package of protections, Curr says. “A correctly applied and maintained coating system manages moisture absorption and keeps the joinery stable. Climatic extremes in humidity and UV can make timber extra susceptible to things like mould, drying and cracking, but quality, well maintained coating systems can overcome those problems.
“At a minimum for exterior timber joinery, we recommend that windows and doors are primed and protected from moisture well before delivery and installation. We also encourage people to look carefully at the design of their joinery as sharp edges can lead to coating weak spots. Arrised or rounded edges permit greater coverage [of coatings] and reduce the possibility of premature failure and moisture ingress.”
Residential windows and doors often have the most problems, as home owners can lack education about coatings, with some not paying adequate attention to their choice of product. “The performance requirements of an interior and exterior coating are quite different,” says Curr. “Interior coatings are invariably designed to protect only from staining, bumps and abrasion. Exterior coatings systems have to offer the same protections but must also shield against the elements.
“For interior application, the determining factor is more often aesthetic, so oils can offer a more natural look. Non-yellowing water-based polyurethanes provide a more robust finish while still retaining the original colour of the timber. [For exterior application], pigment offers the best shield from the harsh Australian sun and protects the surface structure of the timber, ensuring a sound substrate for the coating to adhere to. Essentially, products that are going to offer the best long-term proposition will have some colour.”
Keeping up appearances
Maintenance is another issue that requires more education for many home owners. There is a common misconception that timber doors and windows require complicated annual upkeep, which has possibly been born of some substandard product in the past.
In fact, upkeep is often surprisingly simple, but relies on end users not being complacent. As Curr says, “Exposure, orientation and product type will all impact the length of the maintenance schedule, this could be from one year, up to over 10 years. The key to low maintenance is minimum 12-monthly inspections and making good any mechanical damage before moisture ingress compromises the integrity of the coating system. Single coat maintenance should be the objective.”
Again, there is an opportunity for timber manufacturers to make sure that product education is passed on through designers and builders to the end user. Knowing that people can be lazy about maintenance, there is good reason to spend more on a higher-grade initial product. “The easiest solution from the end user’s perspective is timber joinery that’s been fully finished by the manufacturer before it’s installed,” says Curr. “This way, people don’t have to wait or arrange finishing themselves. Additionally, when coatings are applied in a factory controlled environment, coverage rates and finish results will tend to be much more consistent providing longer term protection and performance.”
Though there are some local perils that not even the best current technology can fully manage. When asked if there was any solution to seal and frame attacks by cockatoos, Curr wryly suggested wasabi showed promise as a coating.
New on the block
Another sometimes under-appreciated aspect of timber as a door and window material is its enormous adaptability. It can be used to make products that meet standards specifications in an incredible variety of shapes, styles and sizes.
In previous years, that degree of bespoke design came with a Savile Row price tag. But recent technological advances have changed that. Computer controlled woodworking machines and systems mean that small runs are now economical, even for complex shapes and profiles.
Justin Macri uses a Weinig HolzHer ProMaster 7225 5 Axis CNC in his Sydney-based business, Metric Joinery. It’s an investment that has more than paid off for the quality manufacturer. “New CNC processing technology has become more user-friendly, ultimately making small production runs more feasible,” he says. “We use advanced design software, which allows for faster programming times. This, in turn, enables greater flexibility in the products that we offer, including advanced window design and architectural joinery in general, and allows our clients the ability to create their desired product.
“These advances in technology have also proven to be extremely useful in both heritage and contemporary buildings, as timber can be manufactured to match existing designs or to further allow designers and architects to express their visions.
The beauty of the system is that training on the machines is widely available through both institutions and companies, and the process can start with a sketched design just as easily as with a complex rendering. Macri says, “The process begins with the architect’s ideas, which we then implement into our advanced design software, allowing us to see how they can be achieved. Once we complete the software programming, we are presented with a three-dimensional image that allows us to clear up any design flaws and inconsistencies. Software design also illustrates how individual parts will come together to complete the final works.”
But 21st century technology isn’t so different from the traditional methods of joinery that Macri trained in. “It’s still essential to have knowledge of timber selection and grading in order to ensure that our clients receive the best possible product,” he says. “Furthermore, the assembly of individual machined parts to finalise a product has remained a traditional skill.”
That emphasis on timber has allowed Metric Joinery to create a point of difference in their end product. “We predominantly purchase sustainable growth timbers,” says Macri. “We think this is an important area where the industry can educate the general public on the efficiency of timber products as a whole, and the fact that their use is most often environmentally friendly.
“We plan to further incorporate recycled and sustainable growth timbers into our manufacturing process in coming years to ensure the promotion of environmental sustainability.”
On the horizon
It’s not only in the manufacturing process where new technologies are expanding the range of door and window options on the market. Developments in most parts of the process will be coming to market in the next few years.
Gramlick sees AWA members responding to global issues. She says, “With the emerging increasing stringency levels for energy efficiency between 2019 and 2030 in order to meet the Paris Agreement targets, the timber window industry has a huge opportunity to extend the range of efficient glasses used to provide solutions into the future.”
Environmental issues are also front of mind for Curr, who says, “Given the heightened social awareness of safety and sustainability, we also see demand growing in the coming years for environmentally responsible solutions.”
Part of the coatings’ industry’s environmental focus also plays into the truth that homeowners can be a little lazy when it comes to upkeep. Curr says, “We are always looking to develop coatings systems that will offer significantly longer durability and maintenance schedules as we believe that this would encourage the use of timber in many more applications.”
But for the short term, Curr feels the industry is already on the right track to reclaiming its previous dominance in the sector. “We’re seeing more and more Australian manufacturers incorporating factory applied coating practices whether it’s applying a primer, semi finishing or fully finishing,” he says.
“It’s a way of adding value with time/money-saving advantages for builders and end customers alike. They recognise that having more control of their output can deliver a higher quality end product and higher levels of customer satisfaction, which is great news for the industry.”
