Which material, and why
This is the page a competitor would never build, and the one thing you cannot judge by looking at a finished job. Read it before you compare two quotes.
| Material | Where it belongs | Where it fails | Relative cost |
|---|---|---|---|
| Aluminium 6063-T5, powder-coated | Windows, doors, awning frames, anything near the sea | Not structural. Dents. Cannot be welded and repainted invisibly. | 1.0 |
| Stainless SS304 | Outdoor rails, gates, anything touched, wet, or coastal | Expensive. Will still tea-stain if it is never rinsed. | 2.2 |
| Stainless SS201The rule we will not bend | Indoor decorative only, dry, inland | Rusts within a year within about 5 km of the sea. Looks identical to 304 on the day it is installed. | 1.4 |
| Mild steel, hot-dip galvanised | Fences, gates, structure, anything outdoors and heavy | Heavy. The finish is functional, not decorative. Adds 5 days. | 0.9 |
| Mild steel, powder-coated | Indoor structure, and gates you accept repainting | Rusts from inside the tube if the ends are not sealed. This is how most cheap gates fail. | 0.7 |
Relative to powder-coated mild steel at 0.7. Indicative — the material is rarely the whole cost of a job.
Three kilometres from the water
The rule we will not bend
We are 3 km from the water. Salt air decides more about your job than the price does. We will not quote SS201 for anything outdoors. It costs about 40% less than 304, it looks exactly the same when it goes in, and near the sea it will show rust in under a year. If you have been quoted “stainless” and the price seems good, ask which grade. If you want 201 outdoors anyway, we will build it — and we will write on the quote that you asked for it.
3 km · Ban Chang, Rayong
Finishes
| Finish | Use | Note |
|---|---|---|
| Powder coat | Aluminium and mild steel, indoors and out | 18 standard colours held in stock. Anything else adds ฿1,200 and 3 days. |
| Hot-dip galvanise | Mild steel outdoors, before powder coat | Sent out. Adds 5 working days. |
| Wet paint | Repairs and touch-ups only | Never as the primary finish on a new job. |
| Brushed SS304 | Rails, kitchen work, shopfronts | The grain runs with the length. Always. |
| Raw / mill finish | Inside a machine guard, and hidden work | We will not sell it to you as a finished surface. |
Tube ends are sealed on every job, indoors or out. It is listed here because it is the most commonly cut corner in this trade and the one thing you cannot check by looking.
Which do I need?
- “It lives outside, and we are near the sea.”
- Aluminium, SS304, or galvanised mild steel. Never SS201.
- “It has to carry weight.”
- Mild steel. Aluminium is not structural, whatever the section looks like.
- “People will touch it every day.”
- SS304, brushed. It is the only one that still looks right after a year of hands.
- “It is indoors and the budget is tight.”
- Powder-coated mild steel, with the tube ends sealed. That last part is not optional.