It will come as to surprise that there are british standards for powder coating, and that these standards are very strict. This is vital in ensuring that polyester powder paint is not only treated, handled and applied in the correct way, but to ensure that the required industry guarantees on powder coated aluminium can be honoured in the event of a claim.
British Standards on polyester powder paint are covered by BS EN 12206-1:2004
The current standard, Paints and varnishes – Coating of aluminium and aluminium alloys for architectural purposes superseded the well known BS6496 1984. The 2004 BS EN standard covers primarily the very important process of pre-treatment for the extrusions and the requirements for routine sample testing.
The Qualicoat Standard is another key accreditation in polyester powder coating
Qualicoat is the standard to which all the well respected and professional finishers and applicators adhere to and this standard includes the requirements of BS EN 12206-1:2004 completely.
The criteria for becoming a Qualicoat approved applicator is strict. The testing process is extensive and upon accreditation as a Qualicoat Approved Applicator, powder coaters will be subject to unannounced routine inspections and visits to ensure that the Qualicoat standards in architectural powder coating are adhered to. In the event of non conformance, the applicator will lose the Qualicoat licence.
The specification of polyester powder coated aluminium is also important.
Many companies tendering for commercial or residential supply and installation work will be familiar with the powder coating specifications used in tender documents. Similarly aluminium systems companies that supply powder coated aluminium extrusions to their fabricator base must use powder coaters that meet the BS EN and Qualicoat standards. This also applies to aluminium systems companies that may have their own powder coating plants.
The paint quality that will normally be specified will refer to
‘Architectural powder coating to Qualicoat standard from approved supplier’
and may also mention any specific requirements such as marine, chlorine or seaside/coastal environments.
What about the lifespan of polyester powder coating?
It is accepted that all polyester power coatings will suffer the effects of ageing. Much of this can be avoided by routine cleaning, but it is also the case that many buildings once handed over may have their windows cleaned, but little attention will be paid to the cleaning and maintenance of the polyester powder coat itself.
The use of high quality powders, treated to the correct standards and procedures will ensure that the powder coating lasts for the intended length of time.
Responsible architects who are specifying projects that are in extreme environments, high rise or hard to reach applications must ensure that the correct surface finish and guarantee is specified.
The Term “Florida Weather Exposure” is the class of weather exposure for powder coated finishes.
The Qualicoat standards classify the category of exposure of powder coated aluminium under the Florida exposure whereby test samples must retain certain gloss levels on testing. Briefly explained:
- Class 1 – 1 year ‘Florida’ – weather exposure – standard
- Class 1 requires the testing to reveal 50% of the original gloss level at the end of sample testing.
- Class 2 – 3 year ‘Florida’ – weather exposure
- Class 2 requires 75% of the original gloss level at the end of sample testing
- Class 3 – 10 year ‘Florida’ – weather exposure
- Class 3 requires at least 90% of the original gloss level at the end of sample testing.
The use of a professional, accredited and certified powder coater is essential
It is often the case that many fabricators may cut corners by using local painters and applicators that are not Qualicoat approved nor do they coat to the required Standards. Whilst in the very short term a colour match may be achieved, in the longer term, should there be any issues over paint quality on an installation the costs for not using an approved applicator can be very severe.