Why Marine-Grade Matters
Standard zinc-plated steel fasteners last 2-5 years outdoors before significant corrosion. In marine environments (within 5 miles of saltwater), that drops to 6-18 months. Marine-grade fasteners provide:
20-100+ year service life
in marine conditions
Galvanic corrosion resistance
when properly matched to materials
Pitting and crevice corrosion resistance
critical to chloride environments
Aesthetic durability
no rust staining
Recommended Materials
The Marine Standard
316 stainless adds 2-3% molybdenum to standard 18-8 (304) composition, dramatically improving pitting resistance in chloride environments. The premium choice for:
- Boat hardware (cleats, deck plates, hatches)
- Dock construction and pilings
- Marina equipment
- Saltwater pool hardware
- Coastal building applications
Silicon Bronze — Wood Boat Standard
Traditional choice for wooden boat construction. Naturally corrosion-resistant, compatible with wood and copper alloys, with attractive appearance that ages to a deep patina.
- Wood boat construction
- Decorative marine applications
- Underwater applications (compatible with copper-based antifouling)
Hot-Dipped Galvanized — Economic Choice
For non-critical marine applications above the waterline, hot-dipped galvanized fasteners provide 20-50 year service life at a much lower cost than stainless. The thick zinc coating (typically 2-4 mils) protects the underlying steel.
Best for: Marine framing, structural applications, sign mounting, equipment installation where appearance is less critical.
Monel & Inconel — Severe Service
For the most demanding marine environments (offshore platforms, underwater applications, high-temperature seawater), specialty alloys provide ultimate corrosion resistance. Available on special order — contact our sales team.
Application Examples
Sailboat Standing Rigging
- 316 stainless steel turnbuckles, clevis pins, cotter rings
- Match all hardware to 316 to prevent galvanic corrosion
Dock Construction
- 316 stainless hex cap screws for structural connections
- 316 stainless carriage bolts for decking attachment
- Hot-dipped galvanized lag bolts for piling-to-stringer connections
Boat Deck Hardware
- 316 stainless cleats and deck plates with 316 fasteners
- Silicon bronze through-bolts for traditional wood construction
- Phillips/slotted combo for serviceability in remote conditions
Coastal Decks & Outdoor Structures
- 316 stainless deck screws (resist coastal salt air)
- Stainless construction bolts for ledger boards
- Hot-dip galvanized hardware for posts and structural elements
Common Mistakes to Avoid
Mixing stainless with carbon steel
Galvanic corrosion will quickly destroy the carbon steel.
Using 18-8 (304) in saltwater
Will pit and corrode within months. Upgrade to 316.
Standard zinc-plated near the ocean
Even 5 miles inland, salt air accelerates corrosion. Use HDG or stainless minimum.
No isolation between dissimilar metals
When you must mix metals, use plastic washers or isolation tape.
Underspecifying torque
Stainless galls easily. Use anti-seize compound and proper torque values (about 70% of carbon steel torque).
Need Expert Help?
Not sure which material is right for your application? Our engineering team can help match the right grade and finish to your environment. Contact us with:
- Your application (above water, below water, splash zone, etc.)
- Materials being joined
- Load requirements
- Maintenance access (replaceable vs hidden/permanent)