Selecting the Right Hardware for Outdoor Jetties

Outdoor jetties live in a brutal environment where sun, salt, and constant impact conspire to loosen every bolt. Picking hardware that can take that beating without turning into a maintenance nightmare is the difference between a pier that feels solid for decades and one that groans under every footstep.

The choices you make in the fastener aisle echo for years. A single mis-selected screw can force a full deck replacement long before its time.

Match Metal to Water Type

Freshwater Lakes

Standard galvanized coatings hold up well in low-salinity water. Pair them with pressure-treated lumber rated for ground contact and you have an economical system that resists rot and rust. Avoid mixing bare aluminum brackets with galvanized bolts; the galvanic mismatch invites white crusty corrosion that lifts the bracket away from the wood.

Stainless steel is still welcome here, yet its premium cost only pays off when aesthetics matter. A hidden hanger screw that never stains swimwear may justify the upgrade.

Hot-dip galvanized lag screws with a thick, dull-zinc finish outperform electro-galvanized versions. The thicker coating fills thread valleys and buys extra seasons before the first red rust bloom appears.

Brackish Estuaries

Salinity swings demand 316 stainless anything below the waterline. The molybdenum in this grade resists the pitting that starts where salt concentrates at thread edges. Use the same grade for hardware pockets that trap spray yet rarely dry.

Above the splash zone you can drop back to hot-dip galvanized, but isolate it from stainless with nylon washers. The plastic barrier stops the tiny current that would otherwise eat the cheaper metal first.

Coated deck screws labeled “marine” often mean little more than a painted head. Read the fine print; if the shank is only zinc-plated, reserve them for indoor portions of the dock house.

Open Ocean

316 stainless is the baseline, yet even it will tea-stain without periodic fresh-water rinses. Specify fasteners that are passivated and electropolished; the smooth finish denies salt crystals a foothold.

Super-duplex stainless bolts survive where 316 eventually pits, but their price competes with small outboards. Reserve them for critical hinge pins and ladder rungs that you cannot inspect easily.

Never allow carbon-steel washers to touch stainless bolts. The steel rusts first, swells, and locks the joint so tight that future removal requires grinding.

Size for Load, Not Convenience

Deck Board Fasteners

A 5/4 board moves more than you think. Use two #8 stainless screws per joist intersection, driven flush but never countersunk, so the head can still clamp when the wood cups.

Longer screws do not add strength once the thread passes through the opposite layer. A 2-½-inch screw fully engages a 1-½-inch joist; anything longer simply buries unneeded shank.

Ring-shank nails beat smooth shanks for sheer resistance, yet they surrender to seasonal uplift. Screws paired with a nail every third board split the difference between speed and grip.

Structural Posts

Half-inch through-bolts carry the bulk of lateral load from boat wake. Place them no closer than 2 inches to the end grain to avoid splitting, and always use washers large enough to span the wood’s summer swelling.

Carriage bolts look tidy, but their smooth neck can spin in hardwood. Hex-head bolts with a washer under both head and nut allow future retightening without rounding the drive recess.

Hot-dip galvanized washers are stamped from thin sheet and can cup. Flip each washer during assembly; the concave side against the wood bites and the convex side under the nut centers better.

Brackets and Hangers

Manufacturer-supplied joist hangers come with nails sized for interior decks. Swap them for the same diameter in 316 stainless; the hanger fails at the bend long before the nail shears.

Face-mounted stringer brackets need at least four fasteners on each leg. Skimping to two invites the bracket to twist and slice the wood fibers every time a wave slaps the pile.

Use structural screws instead of nails only when you can drive them with a torque-controlled drill. Over-driven structural screws snap the hanger flange, leaving you with a bracket held by half its intended metal.

Coatings That Outlast the Label

Galvanized Layers

Hot-dip galvanizing after fabrication covers cut threads and drill holes. Inspect for drips that formed knife-edge beads; they snap off and leave bare steel spots that rust first.

Mechanically-plated bolts offer a thinner, more uniform coating. They thread easier into pilot holes but sacrifice years of life for that convenience.

Paint over galvanizing only after wiping with a mild acidic etch. Without the etch, paint peels in sheets and hides the tell-tale white rust you need to see.

Epoxy and Powder Coats

Fusion-bonded epoxy on chain and shackles flexes enough to stay intact under load. Scuff the mating surface with 80-grit so the coating can key into the metal pores.

Marine-grade powder coat survives UV longer than liquid paint, yet it chips when struck by anchor chain. Keep a small tin of matching liquid epoxy in the dock box for quick touch-ups.

Two-part polyurethane over stainless handrails prevents the tea-stain film that transfers to dock lines. Apply it in thin coats; thick films crack when the tube flexes under a leaning shoulder.

Sacrificial Anodes

Zinc donuts slipped over steel piles corrode before the hardware does. Replace them when they look like a rough moon, not when they disappear entirely.

Aluminum anodes suit brackish water where zinc forms a passive crust. The crust stops the anode from working and leaves the fasteners exposed.

Never paint an anode; the coating insulates it and turns your expensive stainless into the sacrificial piece.

Fastener Patterns That Stop Squeaks

Deck Layout

Stagger screws along alternate joists so boards cannot slide in unison. The slight offset cancels the harmonic that creates the dreaded dock chorus.

Leave a 3/16-inch gap between boards so debris can wash through. Trapped grit acts like sandpaper, polishing screw heads into knife edges that cut bare feet.

End-to-end board joints need two screws on each side of the seam. A single fastener allows the ends to curl and form a toe-stubbing ramp.

Handrail Attachment

Run handrail bolts vertically through the cap rail instead of horizontally into the post face. Vertical grain holds threads better and sheds water instead of trapping it in the bolt hole.

Counterbore the hole ¼ inch so the washer and nut sit below the rail surface. A stainless cup then hides the hardware and removes a snag point for dock lines.

Bed the bolt in polysulfide sealant before tightening. The sealant keeps the hole from becoming a straw that pulls rainwater into the post core.

Gangway Hinges

Place the hinge barrel on the shore side so the pin can be removed from stable ground. When the pin is on the water side you end up swimming to dismantle the ramp.

Use a stainless cotter pin with curled tails instead of a hairpin clip. Waves jostle the ramp and shake hairpins free; cotter pins stay until you decide they leave.

Grease the pin annually with a calcium-sulfonate complex. The thick grease stays put in summer heat and resists washout during spring melt.

Hidden Fasteners vs. Face Screws

Clip Systems

Hidden clips let deck boards expand on both edges, cutting the risk of end splitting. Choose clips with a stainless spine and a molded polymer wing; the plastic cushions vibration that would otherwise work the metal against the groove.

Clips require tighter joist spacing, usually 12 inches on center. Factor the extra lumber into the budget before you fall in love with a screw-free surface.

Not all grooved boards share the same groove geometry. Buy a sample clip and test-fit on a single board before ordering the entire package.

Plugged Face Screws

Screw-and-plug kits hide fasteners beneath wood dowels cut from the same species. The dowel swells at the same rate as the board, so the plug stays flush through the seasons.

Drill the counterbore deep enough to bury the screw head, but leave 1/8 inch for the glue line. Too shallow and the plug protrudes; too deep and the glue starves.

Orient the plug’s grain with the board grain. A cross-grain plug telegraphs as a dark oval every time the deck dries.

Color-Matched Screws

Painted screw heads hide well on day one, yet UV fades the board faster than the factory coating. Within a year the screw becomes a bright dot on a dull field.

Choose a head color slightly darker than the new board. As the wood silvers the screw blends instead of screaming for attention.

Use a screw with a trim head, not a bugle head. The smaller diameter sinks below the surface and leaves less paint to chip.

Tool Choices That Save Knuckles

Drivers and Bits

Impact drivers speed up long days but can snap small stainless screws. Dial the torque collar to the lowest setting that seats the head, then finish by hand to feel the wood bite.

Use a star-drive bit instead of Phillips. The extra contact points strip less often, saving you from the curse of drilling out a frozen screw.

Keep a dedicated bit for stainless. Galvanized grit carried over from earlier jobs grinds the driver tip round and leads to cam-out.

Pilot Holes

Hardwoods like ipe split if you skip the pilot. Drill a shank-clearance hole in the top board and a smaller pilot in the joist so the threads grip without wedging the lumber apart.

Countersink bits with an adjustable stop let you set every screw to the same depth. Consistent depth keeps the load shared and prevents one fastener from carrying the whole crowd.

Back out a bound screw after one squeak, not three. Re-driving only packs shavings tighter and welds the screw to the wood.

Board Removal Tricks

Hidden-clip decks still need access for a dropped phone or broken pipe. Install one face-screwed board every eight feet as a service panel you can remove without dismantling the field.

Pre-drill those service boards at the shop and plug the holes. On-site you gain all the speed of clips plus an escape hatch when something rolls beneath.

Label the underside of removable boards with a dab of bright paint. Future you will spot the panel fast instead of guessing which board hides the last screw.

Maintenance You Can Actually Finish

Annual Rinse

A quick freshwater rinse in spring flushes salt before the first hot day bakes it into crystals. Use a garden sprayer, not a pressure washer; high pressure drives water past the washer and into the bolt threads.

Pay attention to the shaded north side where spray lingers. That side often looks clean yet hides the first white fuzz of corrosion.

Let the dock dry before you walk away. Trapped water wicks into the bolt hole and starts the very rust you meant to stop.

Retreat and Retorque

Check bolt tightness with a socket, not an impact gun. A click-type torque wrench tells you which bolts have lost preload and which were simply over-driven from day one.

Spot-brush any rust bloom with a nylon wheel, then dab cold-galvanizing compound. The compound buys another season before the rust creeps under the original coating.

Replace a rusted washer instead of the entire bolt. A fresh five-cent washer often restores clamp better than a new twenty-dollar bolt.

Seasonal Swap-Outs

Remove portable hardware like ladder rungs and mooring cleats for winter. Storing them indoors keeps threads clean and prevents ice from expanding cracks.

Coat stored bolts with a light smear of grease and zip them into a cloth bag. The bag breathes enough to avoid condensation yet keeps the grease off the dock box.

Label each bag by location so spring reassembly needs no guesswork. A strip of painter’s tape and a Sharpie beats a pile of mystery bolts on the workbench.