Salt air is the hardest environment we build for.
On a coast, saltwater retention cuts the life of a metal finish by half or more — and a mossed piece makes it worse, because wet moss holds brine against the steel like a sponge. This is how we spec coastal frames, with the honest numbers.
If the piece is mossed or planted
Moss keeps the metal wet, so the finish works hardest here. Whenever new moss goes in, the frame should be inspected and touched up; every 3–5 years the moss comes out entirely so the frame can be wire-brushed and re-coated with cold-galvanizing paint.
| Finish | Life before major inspection | Repair |
|---|---|---|
| Galvanized | 3–7 years | strip moss, wire-brush, cold-galv paint |
| Duplex (galvanized + powder coat) | 10–15 years | same |
| Stainless steel | 30+ years | premium up front, then near zero |
If the piece wears artificial foliage
Artificial foliage holds no water, so the same finishes last two to three times longer. Maintenance drops to a yearly freshwater rinse to wash salt off the metal.
| Finish | Life before major inspection | Repair |
|---|---|---|
| Galvanized | 10–20 years | wire-brush, cold-galv paint |
| Duplex | 20–30 years | same |
| Stainless steel | 40+ years | none worth planning for |
What we recommend
Within sight of the water: artificial foliage on a duplex or stainless frame. It is the difference between a piece that needs a rebuild in five years and one your successor worries about. Mossed and planted pieces belong a street or two back from the spray line, on a duplex finish, with the strip-and-inspect cycle in the calendar.
How the finishes themselves are applied — including the hot-dip kettle — is on how we make our topiaries. For a coastal project spec, from a pair of entrance pieces to a public installation, start with design & fabrication. A real coastal planting we maintain is written up in the Florida beach-coast case.
