Why windows are a different comparison than railings
Unlike our general railing material comparison, window applications weigh thermal performance and frame slimness more heavily — anodized aluminium's lighter weight and slimmer profile options are a genuine advantage for large window systems specifically.
Where steel wins for windows
Security grills (see our window grill guide) are steel's clear strength — the added mass and strength that make aluminium less ideal for large frames are exactly what's needed for a security barrier.
Anodized aluminium's color options
Anodizing offers a broader range of factory color finishes than steel typically does, which matters for buyers wanting a specific color-matched window system across a whole building facade.
A practical combination
Many projects use both — anodized aluminium for the main window frame and glazing system, stainless steel grills for security layered on top — rather than treating it as an either/or choice.