THE RESURGENCE OF
ARCHITECTURAL ANODISING
Back in the 1970’s architectural aluminium, shopfronts, windows
and curtain wall, was available in anodised finishes. These finishes
were limited to silver, bronze and black. In the day, replacement
window companies often offered a silver framed aluminium
casement window set in a hardwood frame. The finish was
exceptionally robust and if you look round today, some of these
home improvement windows are still performing well. So why did
we all but stop using anodised finishes?
Staying with residential home improvement, in the 1980’s the
new material on the market was PVC. Expensive at the time, the
product offered good insulation and promised a long life with
virtually no maintenance. Over the following decade the PVC
revolution decimated the aluminium systems, despite white
finishes becoming available for aluminium in both electrophoretic
and polyester powder coating finishes.
In the commercial aluminium facade market, polyester powder
coating gave architects the ability to use a wide range of bright
colours in their designs. The ability of powder coating to ‘cover
all’, including blemishes in the extrusion seems the perfect finish
and, whilst few people would admit in the industry, aluminium
dies were produced cheaper as the surface finish of the profile
was often to be covered over with a sixty micron coating of ‘paint’.
These same profiles, when used for anodising, often showed
‘die lines’ which whilst not unattractive, specifiers were not
comfortable with. Powder coating quickly became more economic
to apply than anodising and became the finish of choice. In an
interesting turn more recently, the powder coat industry has
introduced ‘anodic’ finishes to mimic anodised finishes.