Home Exterior Inspection Checklist for Bow, Skagit County

Updated August 2026 · Alpine Exteriors · WA contractor license ALPINI751OW

Why This Checklist Matters in Bow and the Surrounding Skagit Valley

Bow sits in a stretch of Skagit County where farmland, tidal water, and forested hillsides all meet within a few miles of each other. That mix creates exterior wear patterns that are different from a dry-climate home or a house tucked deep inland. Homes near Samish Bay and Padilla Bay pick up salt-laden air that speeds up corrosion on fasteners, flashing, and hardware. Properties shaded by fir and cedar along Bow Hill and the Chuckanut foothills stay damp longer after a storm, which is exactly the environment moss and algae need to take hold on roofs and siding. And because Bow sits between the open Skagit flats and the water, wind gusts funnel through with little to slow them down, testing every loose shingle, flashing seam, and deck railing on a property.

Layer on the region's wet season, which typically runs from October through April with long stretches of steady, low-intensity rain rather than short downpours, and you get a climate that rewards slow, steady water intrusion more than any single dramatic event. A gap that would never matter in a dry climate can, after months of Skagit Valley rain, become a rot problem inside a wall or under a deck ledger. Occasional snow and freezing rain in the foothills above Bow adds another stress: ice that forms in gutters or on north-facing roof slopes can back water up under shingles even when the storm itself was minor.

Washington's building and energy requirements also matter here. The Washington State Energy Code sets minimum performance standards for replacement windows and doors, and it factors into decisions about insulation and air sealing whenever exterior work opens up a wall or roof assembly. A seasonal inspection is the cheapest way to catch small issues — a lifted shingle tab, a clogged downspout, a gap in caulking — before they turn into interior damage, mold, or a larger repair bill. This checklist is organized the way we walk a property at Alpine Exteriors: roof first, then water management, then windows and doors, then decks, then siding and trim.

The Checklist

Roof

• Moss or algae patches on shaded or north-facing slopes — moss holds moisture against the roofing material and can lift shingle edges, which is a common failure point on tree-shaded Bow properties.
• Flashing around chimneys, plumbing vents, and skylights — these penetrations are the most common entry point for the steady winter rain typical of this area, even when the shingles themselves look fine.
• Curled, cracked, or missing shingles, or dented and lifted metal roofing panels — wind gusts crossing the open Skagit flats and off the Strait can work loose material that a calmer climate would leave alone.
• Granule buildup in gutters or valleys, and any low spots holding standing water — indicates the roofing is aging or that a valley isn't shedding the volume of rain this region sees each winter.
• Ice damming along eaves after a cold snap — foothill areas near Bow Hill occasionally see enough freeze-thaw cycling to back water up under the shingle line at the roof edge.

Gutters and Downspouts

• Needles, leaves, and debris packed in gutters — fir and cedar cover common around Bow sheds a steady load that clogs gutters faster than in more open, treeless areas.
• Downspouts that dump water within a few feet of the foundation — Skagit Valley soils are often heavy and slow to drain, so water that isn't carried well away tends to pool near crawlspaces and slab edges.
• Sagging sections, separated seams, or loose hangers — the sustained weight of a wet Pacific Northwest winter, plus any accumulated debris, puts real strain on hangers over time.
• Rust streaks or pinholes in older metal gutters — more noticeable on properties within a mile or two of Samish Bay, where salt-laden air accelerates corrosion.

Windows and Doors

• Fogging or condensation trapped between glass panes — a sign the seal has failed, which matters both for water intrusion and for meeting the performance expectations set under the Washington State Energy Code.
• Cracked or missing caulk and worn weatherstripping around frames — wind-driven rain off the bay finds any gap, and a failed seal here is one of the more common sources of hidden wall damage we see on inspections.
• Corrosion on hinges, tracks, and locking hardware — again more common on properties closer to the water, where salt air shortens the working life of exposed metal parts.
• Sills that don't slope outward or show soft, discolored wood — improper drainage at the sill lets water sit against the frame through the long rainy season instead of shedding away.

Decks and Outdoor Structures

• Ledger board attachment to the house, including flashing above it — this connection carries structural load, and prolonged moisture behind a poorly flashed ledger is one of the more serious issues a deck inspection can turn up.
• Rusted or corroded fasteners, joist hangers, and post bases — the combination of near-constant winter moisture and, on island and bayside properties, salt air, accelerates corrosion on hardware that was fine a few years ago.
• Boards that are cupping, checking, or soft underfoot — repeated wet-dry cycling through the rainy season stresses decking material, especially on older or untreated wood.
• Railings or stair stringers that flex or wobble — both a safety issue and something wind gusts can make worse over time if it isn't addressed.

Siding and Trim

• Gaps or cracked caulk at corner boards, window trim, and wall penetrations — these are quiet entry points for moisture that, over a wet Skagit Valley winter, can lead to rot inside the wall assembly long before it's visible from outside.
• Moss or dark algae streaking on shaded siding — shows the wall isn't drying out between rain events, which is common on the north and east sides of tree-covered lots around Bow.
• Woodpecker holes or insect damage — wooded properties in this part of Skagit County see more of this than open, treeless lots, and every hole is a potential water entry point.
• Paint or finish failure, especially peeling near the bottom courses — often the first visible sign that siding is absorbing more moisture than it's shedding.

What to Do if an Item Fails

Not every item on this list means a major repair. Some, like clogged gutters or a little moss on a shaded slope, are routine maintenance if caught early. Clearing gutters, rinsing light moss growth with an appropriate low-pressure treatment, and re-caulking a gapped trim joint are all reasonable do-it-yourself tasks for a homeowner comfortable on a ladder — just avoid pressure-washing a roof directly, since it can strip granules and shorten the roofing's life, and avoid walking a wet, moss-covered roof at all, since it's genuinely slippery footing.

For anything involving flashing, structural connections like a deck ledger, or signs of active water intrusion (staining, soft drywall, a musty smell near an exterior wall), treat it as a repair rather than a maintenance task. Take photos and note the date, both for your own records and in case the damage is later relevant to an insurance claim or a warranty question. Minor flashing or caulking repairs on a roof or around a window often run in the range of a few hundred dollars; a larger repair, like replacing a section of rotted decking or re-flashing a chimney, tends to land somewhere between several hundred and a few thousand dollars depending on scope and access. If a full roof or window replacement is on the table, get more than one opinion — it's a significant expense and the right answer depends on the age and condition of what's already there, not just the symptom you noticed.

One honest caveat: an exterior inspection, whether you do it yourself or hire it out, is a snapshot. It won't catch everything, especially damage hidden behind siding or under roofing material, and a clean-looking exterior doesn't rule out a slow leak that's been running for months. Treat this checklist as a way to catch the obvious and moderate issues on a regular basis, not as a guarantee that nothing is wrong.

When to Call a Professional

Call a contractor rather than tackling it yourself when you see structural movement — a sagging roofline, a deck that flexes noticeably, or a ledger board pulling away from the house. The same goes for any repair that requires working at height on a steep or wet roof, since fall risk is real and not worth taking on without the right equipment. Recurring leaks that keep coming back after a patch usually mean the underlying flashing or roofing system needs a proper diagnosis, not another temporary fix. If a window or door replacement is being considered, a licensed contractor can also confirm what's required to meet the Washington State Energy Code for the new units, which affects both the products available and, in some cases, permitting.

Alpine Exteriors, WA contractor license ALPINI751OW, inspects and repairs roofing, windows, decks, and gutters across Skagit, Island, and Whatcom counties, including Bow, Mount Vernon, Anacortes, Burlington, Sedro-Woolley, La Conner, Stanwood, Camano Island, and Bellingham. If an item on this checklist looks questionable and you're not sure whether it's cosmetic or structural, that's exactly the kind of call worth making before the next storm cycle rolls through.

FAQ

How often should I inspect my home's exterior in Bow?

A walk-around twice a year — once in early fall before the wet season starts and once in spring after it lets up — catches most issues while they're still minor. Properties with heavy tree cover or close to the water may benefit from checking gutters and roof valleys a bit more often, since debris and moss build up faster in those conditions.

Does moss actually damage a roof, or is it just cosmetic?

It's more than cosmetic. Moss holds moisture directly against roofing material, which can lift shingle edges over time and shorten the roof's usable life, particularly on the shaded, north-facing slopes common on wooded lots around Bow. Light growth is manageable with careful, low-pressure treatment; heavier or long-standing moss is worth having a professional evaluate, since removal itself can damage aging shingles if done too aggressively.

Will replacing my windows affect my home's energy code compliance?

Yes — replacement windows and doors in Washington need to meet minimum performance requirements under the Washington State Energy Code, and that can influence which products are appropriate for your home and how the installation is documented. A licensed contractor can walk you through what applies to your specific project.

How does salt air affect homes that aren't right on the waterfront?

Salt-laden air off Samish Bay, Padilla Bay, and the Strait can travel further inland than people expect, especially when it rides in on the wind gusts that regularly cross this area. Homes a mile or two from the water can still see faster corrosion on gutters, fasteners, and window or door hardware than a home in a drier, more inland part of the county — it's usually just slower and less obvious than what a beachfront property experiences.

Schedule an Exterior Inspection

If this checklist turned up a few items you're unsure about, or it's simply been a while since your roof, gutters, windows, or deck were looked at by someone other than yourself, Alpine Exteriors (WA license ALPINI751OW) offers exterior inspections across Skagit, Island, and Whatcom counties — from Bow and La Conner out to Anacortes and Camano Island, and up through Burlington, Mount Vernon, Sedro-Woolley, Stanwood, and Bellingham. Getting ahead of small issues before the next wet season is usually the difference between a routine repair and a much larger one.