Steel, or steel-look?
Aluminium can imitate the colour of steel, but not its lines, its strength or its life. The difference shows the moment you look closely.
A lot of “steel” windows
are aluminium.
“Steel-look” aluminium is sold on the appeal of black, gridded joinery — but it is a different material doing an impression. Aluminium is softer and far weaker than steel, so the sections have to be made thicker to span the same opening. The result reads heavier: wider faces, chunkier mullions, the very thing the steel look is supposed to avoid.
Our profiles are authentic hot-rolled steel — designed and engineered in Switzerland, assembled in New Zealand. Steel is far stronger than aluminium and won’t deform under heat or load, which is exactly why it can be drawn so thin. The strength is what buys the slim line.
Better three
ways at once.
Three times stronger than aluminium. Thermally capable — often without a break. It won’t deform under heat or load, and it outlasts the building around it.
Sightlines aluminium and timber can’t reach. Equally at home on a heritage villa or an ultra-modern form — the one frame that spans both.
Weight you feel in the hand. A heavy steel door swings and settles with a quality nothing else matches. You notice it before you know why.
Steel costs more.
It’s built to show why.
Real steel costs significantly more than aluminium. Each joint is welded, sanded and finished by hand, and the profiles are rarely available off-the-shelf and costly to make. What that buys is a frame that holds a fine line, takes a four-stage corrosion treatment, and is designed to outlast the building around it — backed by a 15-year durability line rather than the decade an aluminium frame is built for.
We are upfront about it. If a project wants the steel look at the aluminium price, real steel isn’t the answer. If it wants the genuine article — the lines, the heft of a heavy door swinging true, a window measured in generations — that is the whole point of building in steel.
The two suites that
set the line.
W20
The slimmest. Single-glazed.
The most slender profile. Solid hot-rolled steel sections with a stepped-leg design and material up to 5mm thick — where sightlines must all but disappear, on internal screens, heritage retrofits and mild-climate openings.
W40
The everyday. Double-glazed.
A balanced profile that reads almost as slim as W20 but takes a 27mm insulated unit. Seventeen hot-rolled sections, classed heavy-duty, capable of tall and expansive openings. The default specification for new-build residential.
What is “steel-look” aluminium?
Aluminium joinery styled to imitate black, gridded steel. Because aluminium is softer and far weaker than steel, the sections have to be made thicker to span the same opening — so it reads heavier: wider faces and chunkier mullions.
Is steel really stronger than aluminium?
Yes — steel is far stronger than aluminium and won’t deform under heat or load, which is exactly why it can be drawn so thin. The strength is what buys the slim line.
How much more do steel windows cost than aluminium?
Significantly more — roughly 2.5–3× aluminium. Each joint is welded, sanded and finished by hand, and the profiles are rarely available off-the-shelf. We’ll tell you in our first call whether steel is the right tool for your project.
How long do steel windows last?
Every unit goes through a four-stage corrosion-protection process and carries the 15-year durability line — a frame designed to outlast the building around it, with a quarterly clean-and-inspect in harsh coastal exposure.
Matching original joinery? See heritage steel windows, or the full FAQ.
Don’t wait. Plan ahead.
Steel joinery is complicated to make — every joint welded, ground and finished by hand. Bring us in early with your architect and the timeline takes care of itself. Specify it at the start, not the end.