Guide
Both make beautiful architectural planters — but they behave very differently. Here's a straight comparison of weight, durability, finish, rooftop suitability, maintenance and cost, so you can choose with confidence.
Choose aluminium when you want light weight (especially on rooftops and balconies), any colour, low maintenance and a clean contemporary line. Choose Corten steel when the brief calls for that warm, weathered rust patina and a heavier, ground-level installation. We make both — and we'll tell you honestly which suits your site.
Aluminium is roughly a third the weight of steel. On structures with load limits — rooftops, podiums, balconies — that's often the deciding factor. Corten is heavier and best suited to ground level or where structure allows.
Corten develops a distinctive orange-brown weathered patina over time — a signature landscape aesthetic. Aluminium is powdercoated to any colour and sheen, including matte architectural and even Corten-effect finishes, with consistent colour matching across a whole project.
Aluminium naturally resists corrosion and won't rust. Corten forms a stable rust layer that protects the steel, but it will stain adjacent surfaces (paving, render) as it weathers and isn't ideal in constant-wet or marine-salt conditions. We detail liners and bases accordingly.
For most rooftop and elevated projects we recommend aluminium for its weight advantage and clean drainage detailing. See how we work on rooftop gardens.
Aluminium is essentially wipe-and-go. Corten needs no coating but should be positioned to manage run-off staining. Both are long-lived when made well.
| Aluminium | Corten steel | |
|---|---|---|
| Weight | Light — ideal for rooftops/balconies | Heavy — best at ground level |
| Finish | Any powdercoat colour & sheen | Weathered rust patina |
| Corrosion | Naturally resistant, won't rust | Stable rust layer; can stain surrounds |
| Maintenance | Very low | Low; manage run-off |
| Best for | Rooftops, balconies, modern schemes | Ground-level landscape, rustic aesthetic |