Clocks fell back on Sunday, November 1. By mid-afternoon the north wall of a cedar-sided Nanaimo house is already in shade, and the boards have not dried since the last shower. The laps that looked silver in September now show a dark line, with green in the shadow where one board overlaps the next.
Steady rain does not rinse that wall clean. It wets the film, and Douglas fir needles and cedar scales caught in the lap hold the water against the wood. Nanaimo receives over 1,100mm of rain a year. Early November is when short days and back-to-back systems stop a shaded elevation from drying. A haze that looked cosmetic in September is a dark lower course by Remembrance Day on Wednesday, November 11, when guests look at the wall beside the door.
This post stays on cedar wall siding: bevel, channel, and board-and-batten on the house. A cedar shake or shingle roof is the shake roof guide. A wood fence is the fence-line guide. The wider September note on vinyl, Hardie, and cedar together is the fall soft-wash guide. The door, the step, and the glass at the entry are the front entry guide. Roofs, gutters, and glass are separate jobs.
Why the laps stay wet once November sets in
A September afternoon still gives a south wall hours of light. After the clocks change, that same wall is in shade by mid-afternoon, and a north face under western red cedar may not see sun at all. Bevel siding sheds water down the face, and it also makes a small shelf at every overlap. That shelf is where November stops being a rinse.
Shade, a low sun, and a board that no longer dries
Rain wets the grain, and the next system arrives before the lap has aired. On a treed lot the canopy does more than the forecast. North Nanaimo and Lantzville often have fir over the side wall. Parksville and Qualicum Beach add Oceanside damp that sits on a west wall after a shower off the water. Ladysmith and homes in Cedar see the same dark laps on a house that misses a dry day.
A downspout that sheets, or a gutter that goes over the lip, feeds one vertical stripe. If the trough is packed with needles, gutter cleaning with a full downspout flush belongs with the wall. The November pack itself is the fir and cedar needle guide.
What collects in the overlap
Cedar scales and fir needles wedge into the shadow line and keep it damp. Moss and a thin algae film take that moisture. A clean lap sheds. A lap with a needle mat stays wet between showers. On channel siding and board-and-batten, the same film follows the reveal.
What held water does to the wood
The lower courses, and the wall under a drip
The bottom boards take splash from the ground and drip from the eave. They stay dark after the upper courses have lightened. A green or black film in that band is algae and mildew on a finish that no longer dries. Moss in the lap is thicker, and it can lift the overlap so the next rain runs back toward the wall.
On a sound roof, growth that sheds onto the siding belongs with moss removal and roof cleaning. Failing shingles, or a shake roof that is already soft, go to a roofer. Cleaning the wall does not repair the roof above it. Grey fascia along that drip is the eave guide.
A dark board is not the same as a soft board
Wet cedar looks darker than dry cedar, and a shaded wall may not dry for a week. A board that stays black through a real gap in the weather, that cups away from the wall, or that gives under a fingernail at the bottom edge, is further along. A wash can lift the film. It cannot put sound wood back where the fibre has failed.
What you can see from the yard
You do not need a ladder. Wet cedar is a poor surface to lean one on, and the laps that matter show from the path. After a shower, walk the side a guest would see and look at the overlap, the bottom course, and the ground under the eave.
- A dark line in every lap. Needles and a green film in the shadow, while the face of the board is only dull. That is held water, not one storm's stain.
- A stripe under one downspout. The wall is being fed. The gutter and the spout come before the siding will stay clean.
- Splash on the bottom course only. Soil, a bark path, or a concrete skirt throwing water back up the wood. The skirt may want a different wash than the boards.
- Paint lifting in the lap, or a board that is soft. A wash will not fasten that board or repaint that face.
- Green on the concrete or stone at the base. That hard surface is a separate pass. It is not a reason to aim a close jet at the cedar above it.
Cedar, paint, and the concrete below are not the same wash
One wall often has bare cedar, painted cedar, and a concrete or stone skirt on the same afternoon. Soft washing versus pressure washing is the wider method note. On this wall the surface decides which one leads.
| What you see from the path | What it usually means | Sensible next step |
|---|---|---|
| Dark film or green in the laps of sound cedar | Algae and needles on a board that no longer dries | Soft-wash the growth. Keep the rinse gentle |
| Moss packed in the overlap | Growth holding water against the lap | Treat, then a low-pressure rinse. Do not dig the lap with a jet |
| Painted or stained cedar with film on the finish | Growth on a coating that is still in place | Soft wash only. High pressure feathers paint and raises the grain |
| A green skirt of sound concrete or stone under the boards | Algae on a hard surface, often fed by splash | Treat, then pressure where the concrete is sound. Keep that jet off the wood |
| A soft, cupped, or split board, or paint that has left the lap | The wood has moved past a wash | See a carpenter or a painter first |
| A dark stripe only under a gutter or a roof edge | The wall is being soaked from above | Open the gutter and downspout, then wash that run |
What a careful clean looks like
Early November still has mild gaps between systems. Rain mid-visit rinses a treatment off before it has worked, so the day has to leave time for the solution to sit, then a rinse. House washing on cedar is soft washing: an eco-friendly biodegradable solution at low pressure, time to work, then a controlled rinse. That is the method for moss, algae, and mildew on the boards, including painted cedar.
Treat the growth, and keep the jet off the lap
Pressure washing belongs on sound concrete, brick, and durable stone at the base, after the film has been treated. On the cedar it raises the grain and drives water behind the overlap. It is the wrong tool for the boards, for soft wood, and for paint.
A sensible order when the wall is being fed
- The water path first. If a gutter dumps onto the wall, flush that downspout before the siding is the finished surface.
- Roof growth next, if it sheds onto the boards. On a sound roof, moss removal and roof cleaning come before the wall will stay clean.
- Loose needles off the laps and the sill, without prying a board or packing debris into a vent.
- The cedar, solution where the growth is living, then a gentle rinse from the top down so dirty water does not restreak a lower course.
- The hard skirt last, if it is sound, with pressure kept off the wood. Window washing waits until the wall has stopped dripping.
Name a pond, a rain barrel, or a bed at the base before the rinse. The garden, pets, and rain barrel guide is the longer note.
What a wash will not fix
A clean wall is easier to live beside through a dark month. It is not a repair, and it is not a new finish.
Soft wood stays soft wood
A board that is punky at the bottom, a lap that has opened, a split that goes through, and caulking that has left the trim are contractor work. If the bottom course already gives under a light press, book the repair first. Washing a failing board can lift more of the fibre. Cleaning is not siding repair, and it is not paint.
Film is only one reason a wall looks tired
Weathered cedar greys again, and needles keep falling through November. A north wall under fir will grow a new film. This month is a reset before the dark wet stretch, not a bare board until spring. A wash does not stop splash from a packed gutter. If Remembrance Day week is solid rain, book the next opening so the solution has time to sit.
Questions from the yard
Will November rain wash cedar siding clean? Rain moves loose needles on the face and wets the film in the lap. A wall that looked dusty in September can be dark in the overlaps by the second week of the month.
Can a close jet replace a treatment? On sound concrete at the base, pressure lifts dirt after the growth has been treated. On cedar it raises the grain and drives water into the lap. The boards take soft washing.
The fence was done in October. Why is the house still dark? A fence wash stays on the fence boards. The siding is a different surface, with laps that hold needles, and November has added shade and splash since that visit.
Is a dark lower course always rot? Wet cedar reads darker, and a film can look like a failed board. Soft fibre, a board that cups hard, or paint that has left the lap is the repair. The film on sound wood is the wash.
Book the cedar before the long weekend
After the next shower, look at the laps on the side guests will see. Green in the overlap, a dark bottom course, or a stripe under one downspout is the November problem on cedar wall siding. Book that face while a mild gap still exists. A soft board or a joint that has opened goes to a contractor first. Cleaning is not that repair.
On the quote form you can choose House Washing / Soft Washing, Roof Cleaning & Moss Removal, Gutter Cleaning, Window Washing, Pressure Washing, Commercial Services, Multiple Services, or Not Sure — Just Need a Quote. Ground-level photos of the laps, the bottom course, any stripe under a gutter, and the concrete or stone at the base help us size the job before we arrive. Note whether the cedar is bare, stained, or painted, and whether a plant bed, a pond, or a rain barrel sits against the wall. We serve Nanaimo, Parksville, Lantzville, Ladysmith, Cedar, Qualicum Beach and surrounding central Vancouver Island communities, fully insured, with eco-friendly biodegradable soft-wash solutions where the growth needs treatment before a rinse. House jobs start from residential services.