The short answer
Surface oxidation and deposits can usually be removed and the metal polished back. Shallow pitting can often be improved. Deep pitting, corrosion that has eaten into the metal, and peeling or failed coatings cannot be cleaned away and need refinishing or replacement.
What you are seeing
| Appearance | Usually means | Recoverable? |
|---|---|---|
| Dull or chalky surface | Oxidation or weathered finish on the surface | Usually, with cleaning and polishing |
| Streaks on glass below | Oxidation washing down from the frame | Yes; clean the metal and the glass |
| Shallow pitting | Oxidation that has started into the surface | Often improved; not always fully |
| Deep pitting or corrosion | Metal lost to corrosion | No; refinish or replace |
| Peeling or flaking coating | Coating failure | No; refinish |
Why it matters beyond looks
- Oxidation washing off frames stains the glass below and adds to mineral buildup
- Once oxidation takes hold, restoration or replacement becomes the only option
- Entrances and storefronts are the most visible metal on the property
What restoration involves
- Scratch and scuff removal from doors, rails and panels
- Sanding, buffing and polishing matched to the metal: aluminum, brass, bronze, stainless steel
- Cleaning the glass the oxidation has stained
- A maintenance plan so it does not come back
Test a small, inconspicuous area first, and check it before treating the rest.
Keep it from returning
- Include frames and mullions in routine window cleaning
- Add metal to a maintenance plan, especially at entrances
- Ask about protective treatments. See what protective coatings prevent and what they don't.
S&K restores architectural metals and keeps them in condition. See glass and metal restoration.
Not sure what you are looking at? Use the glass and metal damage triage guide, read the full Facade, Glass, and Metal Restoration guide, or have our team assess the surface and recommend the right approach, in writing.
