How to Inspect Your Vancouver, WA Home for Dry Rot (Annual Checklist)

If you own a home in Vancouver, WA, dry rot is one of those problems where everything seems fine until it isn't — and by then, the repair has gone from a few hundred dollars to several thousand. The Pacific Northwest's combination of 37+ inches of annual rainfall, mild temperatures between 40°F and 90°F, and the shade that mature Douglas firs and Western red cedars provide creates ideal conditions for the wood-destroying fungi that cause dry rot.

The name is misleading: dry rot doesn't happen in dry conditions. The term refers to the dry, crumbly texture of wood after the fungus has consumed it. The actual cause is excess moisture that lets fungal spores — which are everywhere in our environment — germinate and start breaking down wood fibers. Once it takes hold, untreated dry rot can spread several inches per month during the wet season.

The good news is that dry rot is preventable, and catching it early means a $500 repair instead of a $5,000 reconstruction. This guide walks you through the inspection we'd do on our own homes — room by room, what to look for, and when to call in a pro.

Before the checklist, know the signs. Dry rot has three calling cards:

**The poke test** — Push a screwdriver or awl into suspect wood. Healthy wood is firm and resists penetration. Rotted wood feels soft, spongy, or gives way entirely. This is the single most reliable field test.

**Visual cues** — Paint bubbling, cracking, or peeling in a specific area. Wood that looks darker or discolored compared to surrounding boards. In advanced stages, wood develops a blocky, cube-like cracking pattern (called "cubical rot") that breaks apart in chunks.

**Smell** — A musty, damp, mushroom-like odor in enclosed spaces (crawl spaces, under sinks, behind cabinets) often means active fungal growth, even before you see visible damage.

If you want a deeper dive into causes and repair costs, our [Dry Rot in Vancouver, WA guide](/blog/dry-rot-repair-prevention-vancouver-wa) covers that in detail. This post is the inspection checklist that complements it.

Block off 30 minutes once a year — ideally late spring after the wet season, with a backup pass in early fall before the rain starts. Carry a flashlight, a screwdriver, and your phone for photos.

**1. Exterior windows and door frames.** The #1 entry point for moisture in PNW homes. Probe the bottom corners and sills of every exterior window with your screwdriver. Check caulking at the trim-to-siding seams and at the window-to-trim seams — if it's cracked, peeling, or pulling away, water is getting behind. Pay special attention to south- and west-facing windows that take the brunt of sun and wind-driven rain.

**2. Decks and railings.** PNW decks are the second-most-common dry rot location. Probe deck posts where they contact concrete footings or the ground. Probe the joists at the rim where they meet the house — water sheets down the siding and pools here. Check stair stringers and the boards directly under planters or grills. If your deck is over 10 years old and you've never had it inspected, this is where to focus your time.

**3. Siding and trim.** Walk the perimeter slowly. Look for paint bubbling (water trapped behind the paint film), warped or cupped boards, and any dark vertical streaks that suggest water tracking down behind the siding. Pay attention to where siding meets the roofline (kickout flashing failures show up here) and where siding meets concrete or grade (less than 6 inches of clearance is a red flag).

**4. Crawl space and foundation.** Most homeowners never check here, which is exactly why it's where extensive rot hides. With a flashlight, inspect the moisture barrier (should be intact and covering all soil), the rim joists at the perimeter, and the mudsill where the framing meets the foundation. A musty smell or visible standing water means stop and call a pro.

**5. Bathrooms.** Probe the floor at the base of every toilet, around tub/shower enclosures, and under vanity cabinets. Slow plumbing leaks cause interior dry rot that doesn't show up on the surface for years.

**6. Roof eaves, fascia, and soffits.** Look up. Fascia ends where gutters terminate, gutter overflow points, and soffit vents are common rot spots. Discolored fascia paint or visible warping = probe it next time you're on a ladder.

**7. Hose bibs, dryer vents, and exterior penetrations.** Every place where something pokes through the siding (faucets, A/C lines, dryer vents, electrical conduit) is a potential moisture entry point if it wasn't sealed properly. Check the caulking/sealant at each penetration.

DIY inspection is great. DIY repair is where homeowners often make it worse.

Call a pro if you find any of the following:

- **Soft wood that extends more than 2-3 inches.** Surface patching with epoxy or wood filler over rotted structural wood is a temporary cosmetic fix at best, and it traps moisture and accelerates the underlying rot. - **Visible fungal growth.** White, gray, or rust-colored fibrous growth on or behind wood means the fungus is actively feeding. Removing it properly means cutting back to solid wood, treating the surrounding area, and addressing the moisture source. - **Musty smell in an enclosed space.** Crawl spaces, basements, behind cabinets — if you can smell active rot, the damage is usually well beyond what's visible. - **Rot near structural elements.** Mudsills, rim joists, deck ledger boards, post bases. These are load-bearing — proper repair often requires temporary support during the work. - **Pre-listing or pre-purchase situations.** If you're selling and want to address rot the right way (so it doesn't show up on the buyer's inspection), or you're buying and the inspection report mentions "possible moisture damage," get a contractor's assessment before signing anything.

The pattern we see most often: a homeowner finds a small soft spot near a window, patches it with wood filler and paint, and three years later we're rebuilding the entire wall because the moisture source was never addressed.

When we're called for a dry rot repair, we don't just replace the rotted wood. We do three things every time:

1. **Find the moisture source.** This is the step most contractors skip. If water keeps reaching the wood, any repair fails within a few years. We look at flashing, caulking, drainage, grade clearance, and gutters to identify why the rot started — and we fix that first.

2. **Remove all affected material back to healthy wood.** We probe and cut until we hit firm, structurally sound material. Leaving even a small section of compromised wood lets the fungus re-establish.

3. **Rebuild with properly sealed, properly flashed materials.** New trim or framing goes in with appropriate flashing, modern caulking, and where applicable, a fresh weather-resistant barrier. Then primer, paint, and a workmanship warranty.

This approach costs more than a cosmetic patch upfront and saves money over the long term — because it actually solves the problem.

Found a soft spot during your annual walk-around? Smelled something musty in the crawl space? Worried about a window that's been peeling paint for two years?

CRM Services offers free dry rot inspections throughout Vancouver, WA and Clark County. We'll probe the suspect areas, identify the moisture source, scope the repair, and give you an honest estimate. No pressure, no upselling — just a clear picture of what you're dealing with.

Call (503) 898-0276 or request an estimate online. We typically respond within one business day.