Why steel gets specified
Impact resistance. A limb that would fold an aluminum gutter will dent a steel one. On wooded lots in Wildwood, Eureka and Town and Country that occasionally justifies it.
Span. Steel holds a straighter line over long unsupported runs, which matters on commercial box gutter.
The rust reality
Galvanized steel rusts from the inside, where the zinc gets scratched during fabrication or worn by grit moving through the trough. By the time you see rust on the outside, the bottom is already compromised.
That's why so many 1950s and 60s homes in Granite City, Hazelwood and Overland have rusted-through steel with a permanent orange stain on the siding below it.
Galvalume
Galvalume — an aluminum-zinc coating — substantially outlasts plain galvanized and is what we use when steel is the right material. It still isn't aluminum for corrosion resistance.
For a homeowner asking about steel because they want durability, aluminum in .032 is usually the better answer at lower cost.
Commercial box gutter
This is where steel genuinely earns its place: heavy-gauge fabricated box gutter on apartment buildings, warehouses and churches, where the span and the water volume are beyond residential profiles.
See our commercial page for how those systems are sized.
Questions people ask
Do steel gutters rust?
Galvanized will, eventually and from the inside. Galvalume lasts much longer but isn't immune.
Is steel stronger than aluminum?
Yes, meaningfully. That's the reason to choose it.
Should I replace my old steel gutters with steel?
Usually not, on a house. Aluminum in .032 is cheaper, won't rust, and lasts longer in residential service.
Do you do commercial steel box gutter?
Yes, fabricated to the building. That's standard commercial work for us.
Free estimate
We measure, we look at the fascia, and you get a number in writing.
Talk to a real St. Louis gutter company
Third generation, family-run since 1947. Somebody picks up, day or night.