It is the question every island homeowner faces eventually: patch the roof one more time, or bite the bullet and replace it? Get it wrong in either direction and you lose money — pouring cash into a roof that is beyond saving, or tearing off one that had a decade left. This guide gives you a clear framework for deciding, calibrated to the specific realities of roofing in the San Juan Islands. Start With Three Questions Before you look at a single estimate, answer these. They resolve most cases on their own. 1. How old is the roof? Age is the strongest single signal. Asphalt shingles on an island typically last 15 to 25 years, less if moss has been neglected. Standing-seam metal can run 50 years or more. If your asphalt roof is past 20 and giving you trouble, you are usually replacing. If it is 8 years old with one leak, you are almost certainly repairing. 2. How widespread is the damage? A single leak at a flashing detail is a repair. Water showing up in several places, sagging areas, or daylight through the deck point to systemic failure. Localized problems get fixed; widespread ones get replaced. 3. What condition is the deck in? If the wood decking beneath the roofing is rotted or soft — a real risk after years of moss holding moisture on shaded north slopes — patching the surface solves nothing. Deck rot almost always tips the decision toward replacement. The Decision Table Use this to place your situation. Ranges are an estimate, not a quote, and reflect island pricing including ferry logistics — crew and material staging plus off-island disposal — which add roughly 10 to 25 percent over a comparable mainland job. Situation Repair Replace Estimated Cost One isolated leak, roof under 15 yrs ✔ $450 – $3,500 Moss present, no deck damage yet ✔ (treat) $400 – $1,600 Multiple leaks, roof 20+ yrs ✔ $11,000 – $40,000+ Rotted or sagging deck ✔ $11,000 – $40,000+ Failing flashing, sound roof ✔ $450 – $3,500 Frequent repairs, rising cost ✔ Asphalt $9k–$24k / Metal $14k–$45k+ Flat section, aging membrane ✔ or ✔ $8,000 – $26,000 When Repair Is the Right Call Repair wins when the roof is fundamentally sound and the problem is contained. Classic repair situations on island homes include: A leak traced to worn flashing around a chimney, skylight, or vent. Wind damage on the west side that lifted or tore a small area — island wind runs roughly 20 percent stronger than Anacortes, so localized wind damage is common. A cracked valley or a few displaced shingles. Moss that has taken hold but not yet rotted the deck. In these cases a targeted repair, plus preventive steps like ice-and-water membrane at the fixed valley and zinc or copper ridge strips to slow moss, buys you years at a fraction of replacement cost. When Replacement Is the Right Call Replacement wins when repairs are chasing a losing battle. Signs it is time: The roof is at or past its expected lifespan. You are repairing the same roof year after year, and the costs are climbing. Leaks appear in multiple, unrelated locations. The deck is soft, sagging, or rotted. Granules are washing into the gutters in quantity, or shingles are curling across whole slopes. Think in cost-per-year, not sticker price A $2,500 repair that buys two years costs you $1,250 a year. A $28,000 standing-seam metal roof that lasts 50 years costs $560 a year — and it is the best long-term island roof, resisting salt air, wind, and moss when built right. When you find yourself repeatedly repairing an old roof, the "cheaper" repair is often the more expensive choice over time. Island-Specific Factors That Tip the Balance A few things weigh more heavily here than on the mainland: Salt air. Near saltwater, corrosion attacks cheap fasteners and coatings. If a repair means matching an aging, already-corroding system, replacement with 24-gauge marine-grade metal and PVDF (Kynar 500) coating may make more sense sooner. Ferry logistics. Mobilizing a crew and staging materials on-island carries fixed costs. If you are going to pay to get a crew out for major work anyway, doing the job once and completely often beats repeated trips. Moss and rain. With 40 inches of rain a year and heavy November downpours, a marginal roof degrades fast. Deferring replacement on a failing roof risks deck rot that raises the eventual cost. Homeowners weighing these factors and searching for guidance on https://sanjuanroofingco.com/ should get a professional inspection before deciding — the deck condition in particular is hard to judge from the ground, and it frequently settles the question. A Simple Rule of Thumb If your roof is young and the damage is localized, repair. If your roof is old and the damage is widespread — or the deck is compromised — replace. When you are genuinely on the fence, weigh cost-per-year and the island's harsh conditions, both of which tend to favor doing the job right rather than patching indefinitely. The Bottom Line There is no universal answer, but there is a reliable method: assess age, extent of damage, and deck condition; place yourself on the decision table; then think in cost-per-year rather than sticker shock. Do that honestly, factor in salt, wind, moss, and ferry logistics, and you will spend your roofing dollars where they actually protect your home. About the Author Nathan Prewitt is a Salish Sea building inspector who has evaluated hundreds of roofs on the question of repair versus replacement. He specializes in helping island homeowners read the true condition of an aging roof before they commit to a decision.
Hiring a roofer in the San Juan Islands is not a decision to make on a handshake and a low bid. Your roof faces roughly 40 inches of rain a year, salt air that eats cheap fasteners, and west-side winds that run about 20 percent stronger than the mainland. The wrong contractor can leave you with a roof that fails years early — and getting a crew back across the water to fix it is a headache you don't want. The good news: a handful of sharp questions will separate the professionals from the pretenders before you ever sign. Ask these eight, and listen carefully to how they answer. 1. Are You Licensed, Bonded, and Insured in Washington? This is non-negotiable. A legitimate roofer carries a Washington contractor registration, a bond, and both liability and workers' compensation insurance. If a worker is hurt on your property and the contractor isn't covered, that liability can land on you. Ask to see current certificates, not last year's, and confirm the coverage is active. Anyone gathering information about https://sanjuanroofingco.com/ should treat proof of licensing and insurance as the very first filter — everything else is moot if a contractor can't clear this bar. 2. Do You Have Experience Roofing in the Islands Specifically? Island roofing is its own discipline. A mainland crew may be excellent in Bellingham and still underestimate ferry staging, off-island disposal, salt-air corrosion, and the moss that thrives on shaded north slopes under the firs. Ask for island addresses they've worked on. A contractor who understands the local climate will talk fluently about corrosion-resistant fasteners, marine-grade coatings, and scheduling around dry weather windows. 3. What Materials Do You Recommend for My Home, and Why? A good roofer tailors the recommendation to your site — proximity to saltwater, slope, shade, and budget. Near the water, you want 24-gauge marine-grade Kynar 500 / PVDF coatings and corrosion-resistant fasteners. On shaded slopes, zinc or copper ridge strips help slow moss. At valleys and eaves, ice-and-water membrane is essential. Watch how they answer. A pro explains trade-offs; a salesperson pushes one product regardless of your situation. Material Best Fit Rough Lifespan Standing-seam metal Long-term island performance, waterfront homes 50+ years Asphalt shingle Budget-conscious, sheltered sites 15–25 years Cedar Traditional look (demanding in wet climate) Varies; high maintenance Flat systems (TPO/PVC/EPDM/torch-down) Low-slope sections 15–30 years 4. How Do You Handle Ferry Logistics and Disposal? This question tells you instantly whether they've done island work. A seasoned contractor will describe how they stage materials in a single well-planned crossing, book commercial ferry reservations ahead of peak season, and haul tear-off debris back to a mainland transfer station. These realities add roughly 10 to 25 percent over a comparable mainland job — and a contractor who can't explain that premium probably hasn't accounted for it, which means surprises later. 5. Can You Provide a Detailed, Written Estimate? Never accept a number scrawled on a business card. A proper estimate itemizes labor, materials, tear-off and disposal, flashing and underlayment, and any decking repair contingency. It should also note that prices are an estimate, not a quote, until the roof is opened up. Vague bids hide change orders. For planning, here are typical island-adjusted ranges: Project Typical Range Roof repair $450 – $3,500 Moss treatment $400 – $1,600 Asphalt roof $9,000 – $24,000 Standing-seam metal $14,000 – $45,000+ Full replacement $11,000 – $40,000+ Flat roof $8,000 – $26,000 If a bid comes in far below these ranges, ask what's been omitted — usually disposal, marine-grade materials, or proper flashing. 6. What Warranties Come With the Work? There are two warranties to understand: the manufacturer's warranty on the materials, and the workmanship warranty on the installation. The material warranty means little if the installation warranty is thin — most leaks come from workmanship, not product defects. Ask how long the labor warranty lasts and exactly what it covers. Get it in writing, and confirm the company plans to be around to honor it. 7. Who Is Actually Doing the Work, and Who Supervises? Some outfits subcontract everything and send a salesperson you'll never see again. Ask whether the crew is employed by the company, who the on-site foreman will be, and how you'll reach them mid-project. On an island, communication matters more — you can't just drive over to check in. Clear answers here signal accountability. 8. Can You Share References and Recent Local Photos? Finally, ask for references from island homeowners and photos of completed local jobs — ideally roofs a season or two old, so you can see how the work held up through a wet winter. Call the references. Ask whether the crew cleaned up, stayed on schedule despite ferry constraints, and stood behind any issues. A confident contractor hands these over without hesitation. Red Flags to Walk Away From As you work through these questions, certain answers should end the conversation: Pressure to sign immediately or pay large sums up front in cash No physical address or verifiable local presence Reluctance to show licensing or insurance A bid dramatically below every other quote Vague or dismissive answers about disposal and ferry logistics No written contract Putting It All Together The best island roofers welcome these questions because their answers are their advantage. They know the climate, they price honestly, they plan around the ferry, and they stand behind their work. Take your time, ask all eight, and compare not just the numbers but the substance behind them. A roof that lasts 50 years is worth a few careful conversations up front — especially when the alternative is calling a crew back across the water to fix a job that should have been done right the first time. About the Author Priya Nakamura is a Pacific Northwest consumer-advocacy writer who has spent over a decade helping homeowners vet contractors and avoid costly hiring mistakes. She specializes in the due-diligence questions that reveal a tradesperson's true expertise.
10 Roofing Materials Ranked for Salt-Air Durability
Living on the San Juan Islands means living with salt. It drifts off the water on every breeze, settles on every surface, and quietly attacks anything that cannot resist it. Cheap fasteners rust, thin coatings chalk and peel, and porous materials trap the moisture that our roughly 40 inches of annual rain deliver. When you factor in west-side wind gusts about 20 percent stronger than Anacortes and moss creeping across shaded north slopes, the question of which roofing material to choose becomes less about looks and more about survival. This is a ranking of ten common roofing materials by how well they hold up to salt air on the islands. Every material can be made to work with the right details, but some fight the climate and some cooperate with it. How the Ranking Works Salt-air durability comes down to three things: how the material itself resists corrosion and moisture, how its fasteners and coatings hold up, and how easily moss and water can gain a foothold. A material that scores well on all three ages gracefully here. One that fails on even one becomes a maintenance burden. Rank Material Salt-Air Durability Est. Lifespan (islands) Notes 1 Standing-seam metal (24-ga Kynar 500) Excellent 50+ years Hidden fasteners, marine coating, sheds moss 2 Aluminum roofing Excellent 40–50 years Naturally corrosion-resistant, ideal near water 3 Copper Excellent 60+ years Premium cost, patinas beautifully, slows moss 4 Concrete tile Very good 40–50 years Heavy, needs strong framing 5 Synthetic composite Very good 30–50 years Mimics slate or shake, lightweight 6 Architectural asphalt Fair 20–30 years Common and affordable, weak on shaded slopes 7 TPO / PVC membrane (flat) Good 20–30 years For low-slope; seams need quality installation 8 EPDM membrane (flat) Fair 15–25 years Economical flat option, less UV-stable 9 Exposed-fastener metal Fair 25–40 years Metal lasts; the screws are the weak point 10 Cedar shake Demanding 20–30 years with upkeep Beautiful but high-maintenance in wet salt air The Standouts 1. Standing-Seam Metal For island homes, this is the benchmark. Panels run in continuous lengths with concealed fasteners, so there are no exposed screws to corrode. Specified in 24-gauge steel with a marine-grade Kynar 500 (PVDF) coating and corrosion-resistant fasteners, it can last more than 50 years against salt, wind, and rain. Its smooth surface gives moss almost nothing to grip, and a zinc or copper ridge strip discourages what little tries to grow. 2 and 3. Aluminum and Copper Both are metals that shrug off salt by nature. Aluminum does not rust, which makes it a natural fit for homes right on the shoreline. Copper is the aristocrat of the group, lasting well over half a century and developing a protective patina that also slows moss. The barrier for both is cost, but their longevity can justify the investment on an exposed waterfront property. The Solid Middle 4 and 5. Concrete Tile and Synthetic Composite Concrete tile resists salt and fire well and lasts for decades, though its weight demands robust framing that not every island home has. Synthetic composites, engineered to mimic slate or cedar shake, deliver strong durability at a fraction of the weight and much less maintenance than the real thing. Both are worth a look if metal is not your aesthetic. 6 and 7. Asphalt and Flat Membranes Architectural asphalt is the workhorse: affordable, widely available, and good for 20 to 30 years, though it struggles on the shaded, moss-prone north slopes under our firs. For the flat and low-slope sections common on modern island homes, TPO and PVC membranes perform well when the seams are welded properly. If you are comparing bids and researching https://sanjuanroofingco.com/ , pay close attention to who is installing these membranes, because a flat roof lives or dies by seam quality. The Cautions 8 and 9. EPDM and Exposed-Fastener Metal EPDM is an economical flat-roof rubber, but it is less UV-stable and tends to need attention sooner. Exposed-fastener metal is a tempting budget version of standing seam, and the metal itself lasts, but every screw is a penetration with a rubber washer that eventually fails. In salt air those fasteners are the first thing to go. 10. Cedar Shake Cedar is genuinely beautiful and historically at home in the Northwest, but it is the most demanding option on this list. In our wet, salty, moss-friendly climate it requires constant cleaning, treatment, and vigilance to reach the top of its lifespan. Choose it with your eyes open to the upkeep. A Note on Cost and Logistics Rough installed-price estimates on the islands run from about $9k to $24k for asphalt, $14k to $45k-plus for standing-seam metal, and $8k to $26k for flat systems. Ferry logistics for crew, materials, and off-island disposal typically add roughly 10 to 25 percent over a comparable mainland job. These are ballpark ranges, not quotes; complexity, gauge, and coating all move the number. The takeaway is simple. Near saltwater, spend your money on corrosion resistance: the right metal, the right coating, and the right fasteners. That is what separates a roof that lasts a lifetime from one that becomes an annual chore. About the Author Priya Anand is a coastal materials writer who has spent years comparing how building products age in the salt and rain of the Pacific Northwest. She believes the smartest roofing decision is usually the one that never asks for your attention again.
Every roof is really two roofs. There is the part you see, the shingles or metal panels, and the part you do not, the wooden deck beneath it. That deck, also called sheathing, is the structural surface that everything else is fastened to. On the San Juan Islands, where roughly 40 inches of rain falls each year and moisture lingers for weeks, the deck is quietly the most vulnerable and most overlooked part of the whole system. This guide explains what roof sheathing is, how it fails in our climate, and what a proper repair involves. What Roof Sheathing Actually Is Sheathing is the layer of wood panels laid across the rafters or trusses to form a continuous surface. Underlayment goes on top of it, then the finished roofing. Two materials dominate: Plywood, especially exterior-grade CDX, valued for its strength and resistance to delamination when it does get wet. Oriented strand board (OSB), engineered wood chips bonded under pressure, common for its lower cost but more prone to swelling and crumbling if it stays saturated. Older island homes may have solid board (plank) decking instead, dimensional boards laid side by side. Each behaves differently when water gets in, which shapes how a repair is handled. How Island Conditions Attack the Deck The deck rarely fails on its own. It fails because water reached it, and island conditions offer plenty of paths. Persistent Moisture and Rot Wet wood is what rot organisms need. When flashing leaks, moss traps water against shingles, or condensation collects under a poorly ventilated deck, the sheathing stays damp long enough for fungus to take hold. Rot spreads along the grain, softening the panel until it can no longer hold fasteners or bear weight. Condensation From Below A roof cavity that cannot breathe collects water vapor on the cold underside of the deck. Over seasons this soaks into the plywood, delaminates the layers, and rusts the nail tips. This is why ventilation problems and deck problems so often appear together. Salt Air Near the Shore Close to saltwater, corrosion accelerates. Cheap fasteners rust, lose their grip, and let panels shift, which opens small gaps for water. Repairs near the shoreline should always use corrosion-resistant fasteners. Warning Signs Your Deck Needs Attention You usually notice a deck problem indirectly. Watch for: A roof surface that looks wavy, dipped, or sagging between rafters. A soft, springy, or spongy feel underfoot when walking the roof. Water stains on ceilings or in the attic, especially spreading patches. A musty, damp smell in the attic. Daylight visible through the deck from inside the attic. Fasteners backing out or shingles that will not lie flat over a section. Crumbling or dark, discolored wood seen during any roof work. Any of these warrants a look before the next big storm. Homeowners researching https://sanjuanroofingco.com/ should know that the deck almost always needs inspection during a tear-off, because that is the only time it is fully exposed. The Repair Process, Step by Step Deck repair follows a consistent sequence whether it is a small patch or a large section. Expose the area. The finished roofing and underlayment over the affected zone are removed so the crew can see the full extent of the damage. Probe and mark. Using a screwdriver or awl, they test the wood. Soft, punky, or delaminated material is marked for removal; it is common to find damage extends past the obvious stain. Cut out the bad wood. Damaged panels are cut back to the center of the nearest sound rafters so the new panel has solid framing to land on at both edges. Inspect the framing. Rafters and trusses are checked for rot too. Compromised framing is sistered or replaced before new decking goes down. Install matching sheathing. New panels of the same thickness and type are fastened with corrosion-resistant nails or screws, leaving the small expansion gap the panels are designed for. Seal and reroof. Fresh underlayment, ice-and-water membrane at valleys and eaves, and the finished roofing complete the repair. Matching Thickness Matters New sheathing must match the existing deck thickness. A mismatched panel creates a visible ridge or dip in the finished roof and can leave a weak transition. This is a detail worth confirming with your contractor. What Deck Repair Costs Because the deck is hidden until the roofing comes off, its condition is often unknown when you get an estimate. Reputable proposals handle this with a per-sheet allowance for replacement plus a note that additional sheets are billed as found. The figures below are ranges and an estimate, not a quote. Situation Rough Range Notes Small localized deck repair $450–$3,500 Falls within general repair pricing Deck work during full replacement Add-on per sheet Priced as damage is uncovered Full replacement (incl. deck) $11,000–$40,000+ Deck repair budgeted into the job Ferry logistics add roughly 10 to 25 percent over a comparable mainland job, since plywood and crews must be staged and old material hauled off-island for disposal. It is wise to keep a contingency in your budget for deck surprises, because a rotted deck discovered mid-project is common on older island homes. Preventing Future Deck Damage The deck lasts as long as it stays dry. Protect it with the same habits that protect the whole roof: Fix leaks fast. A small flashing or valley leak becomes deck rot if ignored through a wet winter. Keep ventilation balanced. Intake at the eaves and exhaust at the ridge let the deck dry from below. Control moss. Do not let moss mat up and hold water against the roof; treat it early. Use the right membranes. Ice-and-water membrane at valleys and eaves shields the most leak-prone areas of the deck. Inspect after big storms. Catching a lifted panel or damaged flashing early keeps water off the wood. The Bottom Line The roof deck is the foundation everything else depends on, and in a climate this wet it deserves respect. Rot from leaks, condensation from poor ventilation, and corrosion from salt air all target the sheathing, often invisibly, until a soft spot or a ceiling stain gives it away. When damage is found, a proper repair means cutting back to sound framing, matching the original thickness, using corrosion-resistant fasteners, and sealing the area correctly before reroofing. Budget for the possibility of hidden deck work on any older island roof, keep water off the wood through good ventilation and prompt leak repair, and the deck beneath your roof will keep doing its quiet, essential job for decades. About the Author Colin Ashworth is a Pacific Northwest construction writer who came up through framing and reroofing crews before turning to writing. He has a particular fondness for the hidden structural details, sheathing, framing, and flashing, that decide whether a roof survives its first hard winter.