San Francisco has no road salt and no ice, so winter here is not the corrosion problem it is elsewhere. The real winter damage is damp interiors — wet shoes, rubber mats trapping water against carpet, and a car that never fully dries out.
Outside, the specific risk is the first rain after a dry spell, which carries weeks of accumulated airborne grime, and paint that goes months without protection while everyone assumes washing in winter is pointless.
We work every day of the year, 8 AM to 7 PM. Winter changes the scheduling and the priorities, not whether it happens.
Almost everything people worry about in winter is exterior, and almost everything that actually goes wrong here is interior.
Wet shoes and rubber mats. Water goes onto the mat, runs to the edges and sits underneath, held against the carpet by the mat itself. It stays there for days. Repeat that through a whole rainy season and the carpet padding never dries, which is where a musty car comes from. Taking the mats out to dry after a wet week is the highest-value winter habit there is, and it is free.
A cabin that never dries. Every wet coat, umbrella and dog raises the humidity in a sealed car. Without heat and airflow, that moisture condenses on glass and soaks into fabric.
The air-conditioning evaporator. People stop using A/C in winter, and the evaporator stays permanently damp instead of drying out. That is the classic source of the musty smell that appears every January. Running the A/C on fresh air for a few minutes before shutting the car off dries it — and it also demists your glass faster than heat alone.
Extraction takes longer to dry. If you are having carpets or seats extracted in December in the Sunset, that is most of a day with the windows cracked rather than a couple of hours. We schedule extraction jobs earlier in the day in winter for exactly this reason, and we will tell you if the forecast argues for moving the date. The odour guide covers the diagnosis if it has already happened.
It works. We just build flexibility into it.
Interior work goes ahead in almost any weather. Light rain does not affect it, and in a garage or a covered lot neither does heavy rain. Winter is genuinely a good time to book interior work, because that is when interiors take the most abuse and when appointments are easiest to get.
Exterior work moves around the forecast. For an exterior detail, paint correction or a coating, we watch the weather and reach out to reschedule before the appointment rather than turning up in conditions that produce a compromised job. Rescheduling for weather carries no penalty, ever.
Coatings need real planning in winter. The car has to stay dry for 24 to 48 hours after application, and the install itself is 7 to 8 hours or more — a two-day job when correction comes first. Finding that window between November and March means picking dates around a forecast rather than booking the next free slot. If you have covered parking, say so up front; it removes the constraint almost entirely.
Fog counts as wet. For a coating cure window, fog heavy enough to wet the panels behaves like light rain. This is why the neighbourhood matters here — the Sunset can be soaked while the Mission is dry.
We bring our own water and power to every job, so nothing about winter changes what we need from your location.
| When | Do this | Why |
|---|---|---|
| Before the rains start | Get protection on the paint | Winter is when paint spends the most time wet. Bare clear coat is the wrong state to enter it in. |
| After the first proper rain | Wash it | That rain carries weeks of accumulated particulate. It is the dirtiest one of the season. |
| Every wet week | Dry the floor mats outside the car | Free, takes two minutes, and prevents most of the musty-car problem. |
| Weekly in winter | Run the A/C on fresh air for a few minutes | Dries the evaporator, which is where the January smell comes from. Also demists glass faster. |
| Mid-winter | Book the interior detail | Interiors take the most abuse now, and appointments are easier to get. |
| Any time leaves land on it | Get them off | Wet leaves are acidic and hold moisture against the paint. |
| Before spring | Decontaminate and re-protect | A season of rain and road film leaves plenty bonded to the paint. |
None of this needs you to be there. Hand over a key or a gate code — we work in garages, apartment lots, office structures and street spots.
Everyone books detailing in spring and summer, which means winter is when you have the most choice of dates — and interiors need it more then, not less.
Exterior and coating work gets planned around the forecast with you. We would rather move a date twice than do a compromised job, and a weather reschedule never costs you anything.
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8 AM to 7 PM, rain included. Exterior dates move around the forecast, and that never costs you anything.