Short answer: near the sea or under hard sun, the finish matters more than the metal underneath. Ask which standard the coating has been tested to, not just what it is called. AAMA 2605 is the toughest of the three AAMA tiers, Qualicoat Class 3 is the top powder class, and anodising is graded by thickness, with AA25 recommended for marine sites in Australia. Whatever you choose, a canopy and regular washing add years.
What damages a door finish near the sea or in the desert?
- Salt. Chlorides carried in the air settle on the door and attack the coating and anything underneath it. Qualicoat describes coastal exposure as within about 5 km of a coast.
- Sun. UV fades colour and breaks down gloss. Dark colours also get much hotter in direct sun.
- Heat and sand. In the Gulf, high temperatures and wind-blown sand can wear finishes faster.
What are the three common finishes for aluminium doors?
Powder coating is a dry powder sprayed on and baked. It is graded in Europe by Qualicoat classes and in the US by AAMA 2603, 2604 or 2605.
PVDF, or fluorocarbon, coating is a liquid paint based on polyvinylidene fluoride. It is known for holding colour and gloss in strong sun. Finishers such as Southern Aluminum Finishing recommend 70% PVDF finishes for exterior architectural aluminium.
Anodising thickens the aluminium’s own oxide layer instead of adding a paint film. It is graded by thickness.
What do AAMA 2605, Qualicoat classes and AA25 mean?
The AAMA tiers for coatings on architectural aluminium:
| AAMA 2603 | AAMA 2604 | AAMA 2605 | |
|---|---|---|---|
| South Florida exposure | 1 year | 5 years | 10 years |
| Colour change | “Slight” | ΔE under 5 after 5 years | ΔE under 5 after 10 years |
| Gloss retention | Not set | Over 30% after 5 years | Over 50% after 10 years |
| Salt spray (ASTM B117) | 1,500 hours | 3,000 hours | 4,000 hours |
Qualicoat powder classes are tested in Florida for 1 year (Class 1), 3 years (Class 2) and 10 years (Class 3). Class 3 is typically used in extreme locations such as the Middle East. The optional Seaside class doubles the minimum amount of metal etched off before coating, from 1 g/m² to 2 g/m², for sites exposed to salt.
Anodising in Australia follows AS 1231, where the grade is the minimum average thickness in microns: AA10, AA15, AA20 and AA25. AA25 is the grade recommended for severe conditions, including marine exposure.
How are our doors finished?
Most of our doors are finished in fluorocarbon (PVDF) paint. Others use brushed metallic paint, piano lacquer, a printed wood grain or a natural shell face; each door page lists its finish. If your project specifies AAMA 2605, a Qualicoat class or a salt-spray test, tell us when you ask for a quote. We will tell you whether the paint system for your order meets it before you approve the drawing, and we can arrange a third-party test if you need one, usually at the buyer’s cost.
How do you look after a door finish on the coast?
- Shelter the door. A canopy or recess keeps salt, sun and rain off the face. It is the cheapest protection there is.
- Wash it. Rinse with fresh water and a mild detergent, and do not use abrasive pads or solvents. Rain rinses most surfaces, but a sheltered door does not get rinsed, so it needs washing more often. For anodised aluminium in severe conditions, the AWS Australia anodising guide recommends washing at least every 6 months.
- Check the hardware too. Ask what material the handle, lock trim and pivot plates are made of, and whether they are suited to a coastal site.
Sources, checked October 2026: Knotwood, AAMA 2603, 2604 and 2605 comparison; Southern Aluminum Finishing, painting guidelines; Glass Times, Qualicoat classes and Qualicoat Seaside class; AWS Australia, anodising white paper.
Quick answers
Which finish is best for an aluminium front door near the sea?
Ask for a coating tested to a high standard rather than a name. In US terms that is AAMA 2605, which requires 10 years of South Florida exposure. In Qualicoat terms, Class 3 is the top powder class, and the Seaside option adds deeper etching before coating for sites near the coast. For anodising, AA25 is the grade recommended for marine exposure in Australia.
Is PVDF the same as fluorocarbon paint?
Yes. PVDF (polyvinylidene fluoride) coatings are often called fluorocarbon paint. Finishers such as Southern Aluminum Finishing recommend 70% PVDF finishes for exterior architectural aluminium.
How often should a coastal front door be washed?
Regularly, with fresh water and a mild detergent. For anodised aluminium in severe coastal conditions, the AWS Australia anodising guide recommends washing at least every 6 months, and every 1 to 3 months in very severe conditions.