The Portland Homeowner's Month-by-Month Exterior Maintenance Calendar

This is the month-by-month exterior home maintenance calendar we wish every Portland homeowner had when they bought the place. It’s built around real PNW weather: the eight-month wet season, moss spore release windows, fire-season gutter risk, the November atmospheric river cliff, and the booking windows that fill up before homeowners realize they exist.

Use it as a checklist. Most months have two or three specific tasks, each tied to a real PNW reason — not generic “spring cleaning” advice that doesn’t fit the climate.

Quick monthly cheat sheet

Month	Highest-priority tasks
January	Post-storm inspection, ice damage check, indoor catch-up
February	Moss assessment, downspout flush after heavy rain, drain line check
March	Spring moss treatment booking, gutter check
April	Spring gutter cleaning, window cleaning, deck inspection
May	Pressure washing season opens, exterior paint touch-ups
June	House wash, deck staining, second moss check
July	Fire-season gutter check, irrigation audit
August	Pre-fall roof inspection, paint while dry
September	Fall gutter booking, Christmas light booking opens, moss touch-up
October	Fall gutter cleaning, Christmas light install begins
November	Last-call gutter cleaning, storm prep, downspout extensions
December	Christmas light maintenance, winter watch

January — Survive the storm season

January in Portland is when the year’s first major atmospheric river damage usually surfaces. Even homes that did everything right in the fall can have issues after a heavy rain cycle.

• Walk the perimeter after major rain events. Look for water pooling at foundation corners, dark streaks on siding, ice or freeze damage along the eaves, and any visible sagging in gutter sections.
• Check downspout outlets. Make sure water exits at least four feet from the foundation. If your downspouts tie into underground drain lines, listen for water actually moving through the line during heavy rain.
• Indoor maintenance catch-up. Furnace filter, smoke detector batteries, water heater inspection — January is the right month for indoor tasks while outdoor work waits for weather.

February — Moss assessment and drain line check

By February, roof moss spore release is starting to pick up. This is the month to assess what you’re working with.

• Visual roof moss inspection from the ground (binoculars are fine — do not climb a wet PNW roof in February). Note green patches, dark streaks below the chimney, and any obvious mat growth on north-facing slopes.
• Heavy-rain downspout test. During the next steady rain, walk around with an umbrella and watch each downspout. Trickle when it should be flowing? Backed-up underground drain.
• Schedule any urgent repairs. Soft fascia, loose hangers, separated seams — booking now for March work avoids competing with the spring rush.

March — Spring transition begins

March is the swing month. Some weeks feel like winter, some like spring. Plan ahead.

• Book spring moss treatment. The April–May window fills up; getting on the schedule in March secures the right week.
• Mid-spring gutter check. Even on a twice-yearly schedule, peek at the gutters. Catkins start dropping by mid-March, and moss runoff begins in earnest.
• Walk the property line. Tree limbs that grew over the roof during the wet season are visible now without leaves — schedule any limb removal before they leaf out.

April — The spring gutter window

April is the spring equivalent of October. The schedule fills up; book ahead.

• Spring gutter cleaning. Catkins, blossoms, washed-down moss, residual winter debris — this cleaning is just as important as the fall one in PNW.
• First window cleaning of the season. Six months of winter grime, pollen, and rain spotting peak in April. The first wash gets dramatic results.
• Deck and patio inspection. Surface the boards and concrete need before pressure washing season opens in May.

May — Pressure washing season opens

The Portland wet season is winding down (sort of — May can still surprise you), and surfaces finally stay dry long enough for a real wash.

• Pressure washing bookings open. Driveways, walkways, patios, fences. Soft-wash is appropriate for siding and decks; high-pressure is for concrete only.
• Exterior paint touch-ups. Trim, fascia, doors. Painting in May means it cures before the next wet season.
• Roof moss treatment if you didn’t get it done in April. Late spring is still effective, just trim the window.

June — House wash and deck staining

June is often the most reliable dry-weather month for major exterior work in Portland.

• Whole-house soft wash. Removes pollen, algae, and the dirty rain shadow that the wet season leaves behind. Soft-wash with appropriate chemistry; never high-pressure on wood or stucco.
• Deck staining. Decks need to be clean, dry, and weathered just right — June is the sweet spot.
• Second moss check. Catch any spots that didn’t fully clear from the spring treatment.

July — Fire-season gutter check

July is when Portland’s exterior conversation shifts from “rain” to “fire.” This is not an abstract risk — wildfire smoke days and ember-cast events have happened in the metro multiple times in recent years.

• Fire-season gutter check. Dry summer gutters packed with dead Douglas fir needles are an ember magnet. Clear them if there’s any meaningful debris. Homes east of I-205, in the West Hills foothills, and along the Happy Valley ridges are highest priority.
• Roof edge debris. Sweep or blow any dry needle accumulation off the roof itself, especially around chimneys and skylights.
• Irrigation audit. July heat is when irrigation problems surface. Walk every zone.

August — Pre-fall roof and paint window

August is paint weather and inspection weather.

• Roof inspection. Now is when problems are easiest to see and easiest to repair. Loose shingles, exposed nail heads, flashing damage — all should be addressed before fall.
• Continue fire-season vigilance. Especially in August, which has historically been Oregon’s hottest fire month.
• Final paint touch-ups. Anything you want done before the wet season needs to be cured by late September.

September — Booking windows close fast

September is the booking-deadline month for the entire fall calendar.

• Book fall gutter cleaning NOW. October fills up by mid-month. If you wait until late October, you may be on a December schedule.
• Christmas light installation booking opens. Most Portland companies (us included) open the Christmas light calendar around Labor Day. Booking by the end of September secures pre-Thanksgiving install dates.
• Fall moss treatment. A September application primes the roof for the wet season and lets the treatment work through winter.

October — The fall gutter window

October is the most important exterior maintenance month of the entire year for Portland homeowners.

• Fall gutter cleaning. Late October through mid-November is the right window. The Douglas fir needle drop and big-leaf maple leaf drop happen in this stretch.
• Christmas light install starts. Most installs happen between mid-October and mid-November to beat the rain.
• Pre-winter window cleaning. A fall wash gets you visibility through the gray months and lets you spot any seal issues before winter.

November — Last-call month

By November, the booking calendar has tightened dramatically and the weather is turning.

• Last-call gutter cleaning. Final two weeks before Thanksgiving is the realistic deadline. After early December, you’re scheduling around rain.
• Downspout extensions. Make sure water from every downspout actually moves away from the foundation. Add a flex extension at any outlet that doesn’t.
• Christmas light installs wrap. Most installs are complete by Thanksgiving weekend.

December — Winter watch and lights maintenance

December is short-task month. Most exterior work has been done; now you watch.

• Christmas light maintenance. A reputable installer (us included) will return for any bulb or section failures during the lit weeks.
• First storm monitoring. Watch downspouts, foundation corners, and any spots you flagged in October.
• Plan January’s catch-up list. Anything that didn’t get done in November is now a January-March task.

The booking windows nobody tells you about

A few seasonal patterns Portland homeowners learn the hard way:

• Fall gutter cleaning books out by mid-October. Book in September.
• Christmas light installation closes for new customers around mid-October. Book by Labor Day.
• Spring moss treatment fills the April calendar by late March.
• Pressure washing is fine to book day-of in May–September except after a stretch of rain (everyone calls at once when the sun comes out).
• Window cleaning is the most flexible — book a week or two ahead almost any month.

Quick Recap

• The Portland exterior calendar has three non-negotiable windows: fall gutter cleaning (October–November), spring gutter + moss work (April–May), and Christmas light booking (September).
• Fire-season gutter checks (July–August) are real and especially important for homes east of I-205 and in the West Hills foothills.
• Atmospheric river season starts in December — get the fall work done by Thanksgiving or pay for it in spring.
• Moss treatment is most effective in active growth windows (March–May and September), not summer.
• Use this calendar as a checklist month-by-month rather than a vague “spring cleaning” routine — PNW weather rewards specific timing.