At Mayne Inc where we produce the Longboard® products we are a AAMA 2605 certified application premise. This means that all product we powder coat whether it be Longboard products or aluminum for other architectural manufacturers receives pretreatment which will consistently achieve the highest performance standards the industry has developed.
The actual powder paint performance we apply is either to the colour fade and gloss loss specifications of AAMA 2604 at a min or AAMA 2605 depending on customer requirements but regardless of paint quality the pretreatment is always to 2605 standards.
The single most significant factor for corrosion of extruded aluminum based architectural products is the pretreatment in advance of painting. In other words if the product is extremely well pretreated and then a cheap paint is used the effect will be fading and loss of initial gloss but extreme resistance to corrosion.
The vast majority of these products which find themselves in the residential market place are painted in “job shop” type facilities using either wet or powder paint. Typically these facilities paint products of both steel and aluminum substrates. A pretreatment system which will work on either substrate will not be able to deliver top performance in either case. At Mayne we only powder coat extruded aluminum and our pretreatment system is designed to achieve the highest standard in the world for effective pretreatment of extruded aluminum.
In order to help architects and industry professionals like yourself gain clarity on various quality levels available in the market place the American Architectural Manufacturers Association (AAMA) was formed and specifications for a wide variety of products have been developed over time. These specifications are verified by a large range of ASTM testing protocols.
Back to the world of painted extruded aluminum. The industry has three levels of performance specifications, they are AAMA 2603, AAMA 2604 and AAMA 2605. Although there are many different tests for each category the critical ones related to corrosion and colour/gloss retention are essentially this;
AAMA 2603 is a 1 year south Florida exposure test and the test subject must not exceed “minimum” fading. (A very loose definition) this standard must also endure 1000 hrs of the test panel in an accelerated salt spray cabinet without seeing any corrosion. The cabinet is creating an atmosphere of 100 degrees f at 100% humidity and 5% salt solution. Additionally the test panel is scratched to the bare aluminum. To pass there must not be any creeping corrosion in excess of 1 mm from the scratch area and no other blisters arising elsewhere on the panel.
AAMA 2604 moves to a 5 year physical exposure test for fade and gloss loss and in this case there is a specific standard of not more than 5 delta E colour units of shift. The accelerated salt exposure test moves to 3000 hrs.
AAMA 2605 in this case the south Florida test period of natural exposure is 10 years with the same 5 delta E colour shift and gloss loss standard. The accelerated salt exposure moves to 4000 hrs.