Since its invention in the 1950s, the technique known as powder coating has come a long way. Originally conceptualised as a commercial, more efficient way to apply protective and decorative finishes to surfaces as an alternative to paint, in 2023 the applications of powder coating technology are many and span multiple industries. Its ability to significantly enhance a surface’s durability has made it popular in industrial spaces, especially in the automotive and electronics sectors.
It also has several architectural uses: to coat aluminium extrusions, cladding, louvres, window frames, doors, and facades, and provide a long-lasting finish that can withstand exposure to harsh weather conditions and stand the test of time.
When powder coating technology is combined with sublimation technology, you are able to camouflage one product to make it look like another product, through the sublimation process.
When applied to cladding, louvres and joinery – arguably the most common applications of aluminium in residential construction – sublimation can make the metal look eerily similar to everyone’s favourite cladding material, timber.
The Huapai Country Club.
Metwood's products can help building's overcome fire requirements while retaining the appearance of wood.
This is the bread and butter of Metwood, a leader in this specific field and a subsidiary of Aotearoa’s largest powder coating specialist, Powder Coating Group. Director Stuart Wilson says when it comes to aluminium that looks like wood, the possibilities are endless.
“We’re applying Metwood to a lot of aluminium cladding, and louvres, giving clients the benefit of low maintenance requirements. And increasingly we are doing a fair bit of commercial interior applications, including feature walls, ceilings, battens and baffles,” says Wilson. “Often this is done to overcome fire rating issues – substituting timber ceilings for aluminium, but keeping the look of the wood intact.”
As a material, New Zealanders have long had a love affair with aluminium: relatively cheap, manufactured locally and on hand, versatile and reliable, it’s been a staple on construction sites for decades. “It doesn’t warp or twist, it doesn’t expand or shrink, and it doesn’t age like timber either,” says Wilson. “So the ability to take this material and make it look like timber puts it in a new territory where it can be integrated into a build wherever the architect has specified a timber look.”
In this way, Metwood’s products serve not only aesthetic purposes but also functional. It’s clear that New Zealanders are increasingly becoming aware of the benefits of camouflaging aluminium to look like wood – but many may not know how the process works.
Sublimation: the process
The act of applying almost any pattern onto a base coat of powder coating is called sublimation. In order to do that, a photographic image needs to be printed onto a film, and the pattern is then transferred into the powder coating using heat.
“We powder coat a profile in the same way as normal powder coating,” says Wilson, “and then we wrap the film around the aluminium. A vacuum is applied to the surface, and then it goes into a purpose-made high-temperature oven.”
Through the high heat process, the pattern transfers directly from the film onto the aluminium and into the powder coating layer – and just like that, what was at first an ordinary aluminium substrate is now completely unrecognisable in appearance.
“We like to say Metwood’s products have the warmth and beauty of wood with the durability of aluminium,” says Wilson.
The Awatere retirement community in Hamilton.
The durability isn’t the only physical benefit. In addition to being more scratch resistant than standard powder coating, Metwood’s products are customisable and flexible, offer structural strength, are environmentally friendly, and hundreds of finishes are available, including some patina and marble finishes. “Because the images used are photographic images of actual timbers, any photographic image of sufficiently high resolution can be used,” Wilson says.
The company that supplies Metwood with its powder coating solution, Interpon, has always offered a 25-year warranty on its sublimation transfer finishing powder – which is up to 300 times more scratch-resistant than standard powder coating. But this only covers the base coat colour, not the pattern itself.
“We’re really excited to say that we can now offer, through Menphis, our Italian supplier, a 10-year warranty on our patterns – the part of the product that makes it look like wood,” says Wilson. “Having a warranty on the patterns is really significant for us, because it gives our customers the confidence that this product is going to last a long time.”
