Home Exterior Inspection Checklist for Big Lake, Skagit County

Updated August 2026 · Alpine Exteriors · WA contractor license ALPINI751OW

Big Lake sits in a pocket of Skagit County where big second-growth firs and cedars crowd right up to a lot of rooflines, the lake itself keeps the air damp for most of the year, and the Cascade foothills are close enough that a cold snap can bring a dusting of snow or a hard freeze most winters. That combination is harder on a house than people expect. This checklist walks through what to look at on a home's exterior, why each item matters specifically in this area, and what to do with what you find. It's meant to be walked once in early fall before the rains set in and once in spring, plus after any windstorm that drops branches in the yard.

Why This Checklist Matters in This Region

Skagit County gets the bulk of its precipitation between October and April, and Big Lake's setting makes that worse in a few specific ways. The tree canopy around much of the lake keeps roofs and siding shaded and slow to dry out, which is exactly the condition moss and moisture-loving algae need to take hold. A north-facing roof plane tucked under fir trees can stay damp for days after a storm while a sun-exposed roof across town has already dried. That constant dampness works into shingles, fascia boards and siding seams over years, not weeks, which is why small issues are easy to miss until they've become expensive ones.

Wind is the other factor. Storms tracking up from the Skagit flats and Puget Sound funnel through the valley and hit homes near the lake with gusts that loosen shingles, flashing and gutter fasteners, especially on homes with mature trees nearby that shed limbs in the wind. And because Big Lake sits closer to the foothills than the coast, this area sees more freeze-thaw cycling in a typical winter than homes right on the water — enough ice to strain gutters and split caulk joints, though rarely enough snow load to threaten a roof structure outright. None of this is hurricane country and nothing here should be built or repaired as if it were, but the year-round moisture and periodic wind and freeze events are real and cumulative. A homeowner who checks the exterior twice a year catches problems while they're still a caulk tube and an afternoon, not a full re-roof.

The Checklist

Roof

• Look for moss or dark streaking on shaded roof slopes, particularly any section under overhanging fir or cedar branches — moss holds moisture against the roofing material and can lift shingle edges over time.
• Check for curled, cracked, or missing shingles, especially on roof faces that catch wind coming off the lake or the open flats to the west — repeated wind stress works fasteners loose even when a shingle looks intact from the ground.
• Inspect flashing around chimneys, skylights, and roof-to-wall transitions for gaps or rust — these are the most common entry points for the kind of slow leak that shows up as a stain on a ceiling months later.
• Note any granules collecting in gutters or at downspout outlets — heavy granule loss means the roofing has aged past its protective coating in that area.
• Scan for overhanging or dead limbs positioned over the roof — a branch that looks fine in July can come down in a January windstorm and take shingles or a gutter run with it.

Gutters and Downspouts

• Clear needles, cones, and leaf litter from gutters before the fall rains start — Big Lake's tree cover fills gutters faster than most neighborhoods, and a clogged gutter backs water up under the roof edge instead of away from it.
• Check that downspouts discharge well away from the foundation, and further still if the lot slopes toward the lake or a low spot in the yard — standing water against a foundation is a slow, quiet cause of crawlspace moisture.
• Look for sagging gutter sections or pulled-away fasteners — ice buildup in a cold snap adds weight that finishes off a gutter already loosened by wind.
• Confirm splash blocks or extensions are still in place after any storm — they're light and easy for wind or a stray branch to knock loose.

Siding and Trim

• Walk the full perimeter looking for cracked, warped, or separating siding panels, paying extra attention to the shaded, damp side of the house — siding on the sun side often looks fine for years longer than the north or lake-facing wall.
• Press gently on fascia and trim boards near gutters and roof edges — soft or spongy wood means moisture has already gotten behind the surface, usually from a gutter overflow or failed caulk joint above.
• Check caulking around windows, doors, and any place two materials meet — caulk here has a limited service life and freeze-thaw cycling in the colder months accelerates cracking.
• Look for green or black staining low on the siding near the ground or under downspouts, a sign of splashback moisture that can lead to rot in wood-based siding over a few seasons.

Windows and Doors

• Check for fogging or condensation between panes on double-glazed windows — a failed seal lets moist air in and is one of the more common heat-loss issues found under the Washington State Energy Code's requirements for building envelope performance.
• Test that windows and doors latch and seal fully — gaps let in both drafts and the fine, wind-driven rain typical of valley storms.
• Inspect exterior door thresholds and weatherstripping for wear, especially on doors facing the prevailing wind direction off the flats.
• Look at window sills for peeling paint or soft wood, an early sign that water is sitting rather than shedding off the sill.

Decks and Outdoor Structures

• Check deck boards for soft spots, cupping, or gaps that have widened — constant damp shade from lakeside trees keeps deck wood wetter longer than an open, sunny deck across the valley.
• Inspect ledger board attachment and any visible fasteners for rust or looseness — this connection is structural and corrosion here is a safety issue, not a cosmetic one.
• Look underneath the deck for standing water, moss growth, or fungal growth on joists, which points to poor drainage or airflow beneath the structure.
• Check railings and stair connections for wobble — wood movement from repeated wet-dry cycles loosens these joints faster than people expect.

Foundation and Grading

• Walk the foundation perimeter looking for cracks, efflorescence (a white mineral residue), or damp patches — these often trace back to a gutter or grading issue rather than the foundation itself.
• Confirm the ground still slopes away from the house on all sides — settling over the years can flatten or reverse grading, which matters more on lake-adjacent lots where the water table is already higher.
• Check crawlspace vents are clear and unobstructed if the home has one, since good airflow underneath helps offset the area's high ambient humidity.

What to Do If an Item Fails

Not every finding on this list needs a contractor call right away. A gutter full of needles just needs to be cleared. A loose splash block can be reset by hand in five minutes. Minor caulk cracking around a window can often be cleaned out and re-caulked with an exterior-grade sealant as a weekend project, as long as the surrounding wood is still sound. The goal of the checklist is to catch these small items before the next heavy rain turns them into bigger ones.

Items that call for more caution: any soft or spongy wood on fascia, trim, deck framing, or window sills should not just be patched over, since it usually means moisture has already gotten past the surface and the extent underneath isn't visible without opening it up. Moss on a roof shouldn't be power-washed off directly — that can drive water and debris under the shingles and do more harm than the moss itself; a gentler treatment and a plan to address the shade or airflow issue causing it works better. Any flashing gap, active leak, or fogged window unit is worth documenting with a photo and a date so you can track whether it's getting worse before deciding on repair versus replacement.

When to Call a Professional

Bring in a licensed contractor when a problem is structural, involves working at height, or when you're not confident about what's causing what you're seeing. That includes any roof with more than isolated shingle damage, flashing that's separated from a chimney or wall, deck ledger connections that show rust or movement, foundation cracks wider than a hairline, or siding with rot behind it. It's also worth a professional opinion any time you find the same failure repeating in the same spot after a repair — that usually means the underlying cause, often drainage or airflow, hasn't actually been fixed.

Alpine Exteriors works roofing, siding, window, gutter, and deck calls throughout Skagit, Island, and Whatcom counties, including Mount Vernon, Anacortes, Burlington, Sedro-Woolley, La Conner, Stanwood, Camano Island, and Bellingham, and is familiar with how Big Lake's shade and moisture patterns tend to show up on a house differently than they do on a more open lot a few miles away. A walk-through inspection before you commit to a repair is a reasonable way to get a second set of eyes on whether something is cosmetic or the start of a bigger issue.

FAQ

How often should I inspect my home's exterior if I live near Big Lake?

Twice a year is a reasonable baseline — once in early fall before the heavy rains set in, and once in spring once the worst of the winter weather has passed. Homeowners with a lot of overhanging tree cover, which is common around the lake, may want to add a quick visual check after any storm that drops branches or debris, since that's when flashing, gutters and shingles take the most sudden stress.

Why does my roof grow moss faster than a neighbor's roof across town?

It usually comes down to shade and airflow. Roof planes shaded by fir or cedar trees, which is common on lots close to Big Lake, stay damp longer after rain and get less direct sun to dry them out, and that dampness is exactly what moss needs to establish. Trimming back overhanging limbs where practical and keeping gutters clear so water isn't pooling near the roof edge both help slow it down, though they won't eliminate the issue entirely on a heavily shaded lot.

Do I need to worry about wind damage even though this area doesn't get hurricanes?

Skagit County doesn't see hurricane-force wind, but storms moving up through the valley and off the flats can still produce gusts strong enough to loosen shingles, pull gutter fasteners, and bring down tree limbs, particularly on homes with mature trees nearby. The practical response is the same as anywhere with regular wind events: keep fasteners and flashing in good repair and address dead or overhanging limbs before a storm rather than after.

Are window or insulation upgrades worth it for a Big Lake home?

Often yes, particularly on older homes with single-pane or early double-pane windows, since a failed seal or an under-insulated attic works against a home's heating costs all winter in a climate this consistently damp and cool. The Washington State Energy Code sets minimum performance standards for windows and building envelope work on new installations and major remodels, and it's a useful reference point when comparing options, though the right upgrade for a given house depends on its age, orientation, and current condition rather than a one-size answer.

Ready for a Second Opinion?

If this checklist turned up something you're unsure about — a soft spot on the deck, a roof section that never seems to dry out, or gutters that keep failing in the same corner — Alpine Exteriors (WA contractor license ALPINI751OW) can walk the property with you and give a straight assessment of what's cosmetic, what's worth watching, and what needs to be addressed before the next wet season. Reach out to schedule an inspection for your Big Lake home.