The first deck I ever rebuilt as a solo contractor was on Granite Street in Rockport, four blocks from the Atlantic. The previous deck had been pressure-treated southern yellow pine, installed in 1998. By 2010, when I tore it out, the joists were spongy enough that I could push a screwdriver through them without much effort. The hardware was rust-pitted. The decking itself had cupped so badly you could see daylight through the seams.
That deck taught me a lesson I've spent the last fifteen years repeating to clients: on the coast, the species and the hardware matter more than the labor. You can do a perfect job framing a deck, but if you used the wrong wood and the wrong fasteners, you've built something that will fail in ten years instead of forty.
What salt air actually does to wood
The conventional wisdom is that salt air "rots" wood. That's not quite right. What salt air does is hold moisture against the wood for longer, accelerating the freeze-thaw cycles that pull fibers apart. It also corrodes ferrous metal at speeds you wouldn't believe — a regular galvanized nail in Pigeon Cove will be visibly rusting within two seasons.
The result is that lumber on the coast doesn't fail in one dramatic event. It fails slowly, from the fasteners outward. Most rotted decks I've torn out had healthy lumber two inches away from the screws.
Species that hold up
For exterior carpentry within a half-mile of the Atlantic, here's what we actually use, in rough order of preference:
Ipe (Brazilian walnut). Dense, oily, heavy as iron. We've installed Ipe decks on Eastern Point that look identical to the day they were laid down, after 12 years and zero maintenance. The downsides: it's expensive, it dulls saw blades quickly, and it requires pre-drilling every hole. But for a south-facing deck on the water, it's the right call.
Honduran or African mahogany. Beautiful, stable, takes finish well. Slightly more maintenance than Ipe but easier to work with. We use mahogany for exterior doors and window sashes in addition to decking. Sourced from FSC-certified suppliers when possible.
Western red cedar. Lighter, less expensive, and naturally rot-resistant. The catch: cedar is soft, so high-traffic decks scratch and dent. It's our go-to for decks in slightly more sheltered spots — Annisquam, Ipswich, parts of Manchester away from direct exposure.
Alaskan yellow cedar. Harder than western red, with similar rot resistance. Hard to find but worth it for handrails, where the durability matters more than the cost.
What we don't use anymore
Pressure-treated southern yellow pine for any visible exterior carpentry. We'll still use it for buried structural members and ledgers (because the chemistry has improved a lot since the 1990s), but never for decking, railing, or trim. It cups, it splits, and the new copper-azole treatment is brutal on hardware.
Composite decking — Trex, TimberTech, and the rest — has come a long way, and we'll install it when a client specifically requests it. But for a house with character, especially a historic home or a shingle-style cottage, real wood ages into the architecture in a way composites never quite manage.
The hardware nobody thinks about
If you're going to spend the money on a good deck, spend the additional 15% on the right fasteners. We use 316 stainless steel for everything within a half-mile of the water — screws, joist hangers, lag bolts, post brackets, the works. Not 304 stainless, which still corrodes in marine environments. Not hot-dip galvanized, which is fine for inland work but won't last on the coast.
For framing hardware, Simpson Strong-Tie's ZMAX line is the minimum acceptable for exterior framing. For anything within direct salt-spray distance, their stainless line is the only thing we'll specify.
Interior carpentry is different
Most of what I've said applies to exterior work. Inside, the rules change. Salt air still gets in — you can taste it on your lips after a nor'easter — but it's diluted enough that ordinary domestic hardwoods are fine. We use white oak, walnut, cherry, and hard maple for interior cabinetry on coastal homes without any special consideration.
The one exception is wood floors in mudrooms and kitchens that open directly onto exterior decks. There, we recommend quartersawn white oak with a marine-grade conversion-varnish finish. It handles the moisture cycles better than plainsawn lumber, and the finish stands up to wet feet and dog paws.
The bottom line
Building on Cape Ann is different from building inland. Specify the right species, use the right hardware, and don't try to save money on the parts that touch the weather. Done right, a coastal deck should last forty years. Done wrong, it'll be soft underfoot in twelve.
If you're planning a deck or any exterior carpentry within sight of the Atlantic, send us a note. We'll come walk the site, talk through species options, and give you an honest read on what'll last.
— Pete