Anodising and PPC – The most common surface treatments

The choice of surface treatments open to the specifier on aluminium facade elements mainly centre around the use of either anodised or polyester powder coated finishes.

Both finishes have their pros and cons which makes the choice challenging at times.

In more recent times, we have seen coloured anodised finishes taking the higher end residential and commercial markets by storm particularly where the specifier has the opportunity to make a statement of their building. The timeless and enduring character of anodising is attractive to specifier and client alike. The fact that anodising is a process where the finish is integral to the surface of the aluminium, is guaranteed not to fade and will never peel are all factors that weigh in its favour.

As anodising is a ‘dipped’ rather than a ‘sprayed’ process as is the case for polyester powder coating and due to the limitations around the size of the anodising tanks, in many instances anodising isn’t deemed to be appropriate particularly if the design of the building includes large areas of pressed aluminium cladding, fascia’s or soffits where the individual elements could be too large to fit into the tanks. In instances such as this, specifiers generally seem to wish to retain the same surface treatment across all elements of their building and therefore specify polyester powder coating. Although the powder formulation is getting increasingly advanced, there is no exact match for anodising.

Polyester powder coating can be produced in many more colours and gloss levels than anodising which gives the specifier greater liberty should they wish to use colours to enhance the visual appearance of their buildings. The ability to make on-site repairs should they be required is also easier with a powder coated finish.

All in all, not a straightforward choice, but an interesting one at times!