An inspection and rebuild of my aging pier taught me a great deal about materials, design and the importance of a reputable contractor.
All boat owners share a single, critical concern: the safety and security of their boats depend on the condition of the pier they tie to. A pier that fails during a storm can damage boats and put people at risk. Yet most of us give little thought to what makes a pier dependable — the pilings, fastenings, materials and workmanship — until trouble appears. My own pier, after 27 years, began to fail and forced me to learn what matters when you seek a slip, rent a dock for a season, or ride out a storm.
I had assumed my pier was acceptable because it was pressure-treated and had served well for many years. I dive around my boat frequently and checked the pilings often. They were crusted with barnacles like many piers, so I’d tap them to feel for solid wood underneath. A few weeks before I discovered the real problem, I was reassured that the pilings felt sound. Then came the day I noticed the pier sagging underfoot.
At low tide the water clarity and light made inspection possible; I realized I could not see a piling as it descended into the bottom. A section was missing. Above and below the gap the wood looked chewed and tapered; the interior surface was honeycombed. Other pilings showed large bites taken from them as well. While the pier didn’t seem on the verge of instant collapse, it moved much more underfoot than it used to. I began to worry that a tropical storm or hurricane could cause severe damage to the pier and to any boats tied there.
We researched marine contractors and contacted several firms, including Northern Neck Marine Construction (www.northernneckmarineconstruction.com), which provided a bid. I inspected other projects, checked references and verified the contractor’s licensing. We hired owner-operator Frankie Davis, and his crew did an impressive, thorough rebuild. The work convinced me of the value of hiring experienced specialists and paying attention to materials and methods.
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Piers built during the early days of pressure-treating should be approached with caution. Preservative technology and treatment standards have advanced considerably, and older treatments did not always penetrate wood effectively. Today there are rigorous standards and a range of preservative formulas suited to different uses and environments.
Most of the timber used to rebuild my pier came from Wood Preservers Inc. in Warsaw, Va. (www.woodpreservers.com). I spoke with Morgan Wright, the company’s president, who emphasized the importance of wood that meets American Wood Protection Association (AWPA) standards. New treated lumber often bears stamps or labels indicating compliance. While you might not worry about these details for a single overnight tie-up, they matter if you’re entering a long-term lease or planning to ride out storms at a marina.
At the mill, lumber is dried in kilns, then placed in pressurized autoclaves that force preservatives deep into the wood fiber. Treatment does not fully penetrate heartwood, but it reaches several feet from each end; this is why piling caps and painted tops are beneficial after trees are cut for aesthetics. Excess chemicals are drawn out with a vacuum and a heating process follows to lock the preservatives in. These EPA-approved compounds are often green in appearance. Treatments differ by use — for example, CCA for pilings and CA-C for decking — and AWPA specifies preservative concentrations for each application. In saltwater, treated pilings typically have an expected service life on the order of 20–25 years, depending on conditions.
Wood remains a common choice for piers because it is economical, adaptable in the field, easy to fasten and repair, and comes from managed forests where harvested areas are replanted. Alternatives include reinforced concrete piles, steel, and composite materials for pilings and decking. Each material has its own failure modes — for instance, crumbling concrete with exposed, corroded rebar signals structural distress. The aim here is not to endorse one material over another, but to share what we learned about timber piers and indicators of durability across types.
Wright recommended galvanized fasteners for our pier. Some builders prefer nailing deck boards so storm waves can pull them away while leaving expensive substructure intact; others favor screws, which hold the decking but may lift substructure in severe wave action unless proper plank gaps and fastening patterns are used. In sheltered locations wave forces are less of a concern.
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Choosing a good pier builder is essential. Watching Frankie Davis at work made it clear why experience, proper equipment and attention to detail matter in this specialized trade. The pile-driving barge he used included a hydraulic pump, a 30-foot derrick, precise hydraulic controls and anchor cables to position the rig accurately. A hulking driving weight cycles on the derrick, and a steel sleeve “cap” with a replaceable wood cushion protects the piling during blows to avoid splintering.
An auxiliary 12-by-32-foot fiberglass barge carried stringers, planks and additional equipment, while a smaller skiff handled crew and cargo. On many docks, owners cut corners, replacing only visible planks while leaving compromised substructure in place. If you see planks renailed onto old stringers, be suspicious — long screws or through-bolts are usually more reliable where loads and weather demand it.
Often old pilings are rotted through and must be extracted before new piles can be installed. Removing these stumps requires heavy chains, hydraulic pulling power and sometimes jetting mud away from the old piles to break suction. Crews use a powered wand attached to a large gas pump to loosen the bottom, then hoist the rotted piles onto a barge for disposal.
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Be wary when you see a pier where some pilings look new and others are clearly original. Failure often propagates through an entire structure. Piling depth is crucial: the deeper a pile is driven, the more lateral load it can resist from wind and boat forces, and the less likely it is to be pulled by ice or surge. In rocky or root-filled bottoms deep driving can be difficult, so ask about piling depth and the contractor’s equipment before committing to long-term dockage.
Some builders drive butt end first (the wider end down) to reduce the chance of pullout from ice as the mud settles around the pile. Others drive the smaller end first because it’s easier to penetrate obstructions and get deeper seating. Each approach has trade-offs: a tapered pile can leave a void as settling occurs, and wood-boring organisms tend to attack pilings from the mudline upward, so thicker treated sections near the top can prolong service life.
My pier’s shallow-water piles had pulled during past storms because original driving equipment couldn’t reach far enough into the mud. We used jetting and, in some spots, a “man driver” — a heavy cap lifted and dropped repeatedly by crew members — to seat the piles deeper where the large rig couldn’t operate. A reputable builder won’t skimp on driving depth or the required equipment.
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There are additional clues to a well-constructed pier. Straight, plumb pilings indicate careful driving and attention during installation; experienced operators check alignment with levels and correct problems immediately. Properly installed stringers and crossties should be through-bolted to pilings with heavy-duty galvanized bolts and washers; nails alone are insufficient for primary structural connections.
Look at how beam ends and fasteners are positioned relative to the outer pilings. Structural timbers and hardware should be recessed or kept back from the pilings so a boat sliding along a piling won’t be scraped or pierced by exposed ends or bolts. Also note piling height: leaving pilings out higher above the deck makes it easier to inspect for crooked drives and gives a margin for future repairs; cutting pilings flush with the deck can hide problems.
Deck board orientation and end grain show a builder’s attention to detail. Many builders orient boards to minimize cupping and improve drainage; when most planks follow a consistent pattern it indicates thoughtful installation. Finally, cleats and mooring hardware should be attached to substantial supporting structure rather than merely bolted through thin deck material.
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Rebuilding our pier reinforced a simple truth: with the expense and personal value of boats, where you tie up matters. If you plan to stay somewhere for any length of time, or intend to ride out storms, take a moment to evaluate the pier. Check for signs of rot, inconsistent pilings, proper fastenings and clear evidence of a skilled builder. A strong pier protects boats and people and provides peace of mind when weather turns ugly or when an inattentive neighbor makes an unexpected move.
Tom Neale is technical editor for Soundings and lives aboard a Gulfstar 53 motorsailer. You can purchase his book “All in the Same Boat” through his website www.tomneale.com.
This article originally appeared in the February 2011 issue.