A classic car is not just a vehicle you park in a garage. A classic is an investment, a piece of industrial history, and often a piece of family heritage. Leaving storage to chance means rust on the underbody, marten damage to wiring, dull paint, dried-out seals and standstill defects. Six months of incorrect storage. the next season starts with a workshop invoice instead of a drive.
We have been storing collector vehicles in climate-controlled depots since 1991, looking after them year-round and prepping them for the season start. This guide covers the five real risks, the dispatch desk rule of thumb, and the six points by which to recognise a professional storage spot.
Main risk
Humidity + temperature
Daily swings above 8 degrees Celsius and humidity above 60 percent drive condensation, oxidation and interior mould. Within one season, visible damage.
Critical period
From 4 weeks of standstill
From 4 weeks onwards: brake discs lose gloss, tyres develop flat spots, seals dry out. Wintering without a concept is the most expensive option.
The 5 big risks of incorrect classic car storage
Humidity and corrosion
Unheated garages with floor-to-earth contact are the most common trap. Cold outside air, warm vehicle, condensation on underbody, brake discs and cavities. Result: flash rust within 6 weeks, pitting within 12 months.
Temperature swings
Direct sunlight through garage windows or roof lights creates daily heat-cold cycles. Paint loses gloss, clear coat cracks (clear coat pest), rubber seals turn brittle.
UV light and paint ageing
Even indirect UV through glass or open doors destroys the pigments of original paint. Patina vehicles lose irrecoverable value.
Martens and pests
Marten bites on ignition cables or brake lines are not just expensive (3,000 to 6,000 euros for repair), they are dangerous. Private garages are marten hotspots, especially in winter.
Theft and insurance gap
Private garages rarely meet the requirements of classic-car comprehensive cover. In a claim, the insurer reduces payout. Worst case: no replacement.
Requirements for a professional classic car storage spot
We often get calls from collectors looking for damage limitation after improper storage. The most important requirements you should demand from any serious collector depot:
Stable temperature (8 to 15 degrees Celsius)
Active climate control with a maximum 3-degree swing per day. Earth-tempered bunkers also work but are rarely available.
Humidity below 50 percent
Active dehumidifier with continuous monitoring. Silica-gel-based systems work only for small cavities.
24/7 alarm and CCTV
Certified alarm connected to a monitoring centre. Indoor and outdoor CCTV, footage retained for at least 30 days.
Fire protection at commercial standard
Dry-wall construction, automatic fire detection, at least F30 classification, ideally sprinkler-protected. A private garage never meets this.
Rule of thumb from the Classic Car Service dispatch desk
From 50,000 euros vehicle value: climate-controlled collector depot.
Below that, a well-insulated dry hall with base heating may suffice. Above it, professional climate control costs less than the first restoration invoice after wrong storage.
Climate-controlled storage. What does it really deliver?
Climate-controlled does not mean heated. Heating alone is actually damaging: it drops relative humidity too far, seals dry out, interior wood cracks. Professional climate control keeps temperature AND humidity constant. In our main depot in Schwieberdingen we run 12 degrees and 45 percent humidity year-round.
The economic point: one season of wrong storage costs between 2,000 euros (brakes, tyres, battery) and 35,000 euros (paint touch-up, interior restoration, rust remediation). The premium for climate-controlled storage typically pays back in 18 to 24 months.
Checklist: 6 points for professional classic car storage
Have these 6 points confirmed in writing before you place your classic into storage.
Climate log with daily entries
Temperature and humidity are recorded automatically and provided as PDF on request. Mandatory for vehicles relevant to comprehensive insurance.
Insurance explicitly for collector storage
Standard warehouse insurance often does not cover classic cars adequately. Have the cover amount confirmed in writing.
Defined care interval
Weekly visual inspection, monthly battery check, quarterly tyre pressure rotation. Must be contractually stipulated.
Access only by trained staff
No rental garages, no shared storage. Document who moves the vehicle and when.
Photo documentation at intake and release
Complete condition documentation. The basis for any later discussion about damage.
Season-start check included
Before spring release: battery, tyres, brakes, fluid levels, test drive. Avoids the first workshop bill.
Recommissioning after long standstill
Even in a professional depot, recommissioning after a season is not just turning the key. Test the battery first with a maintenance charger. Inspect tyres for flat spots. Test brake fluid water content, often replace after 24 months. Check engine oil, change if cloudy. First drive: 30 minutes unloaded, then add load.
Booking the season-start check as a service avoids the most common standstill follow-ups. We offer it for all vehicles stored with us, optionally for externally stored classics too.
The most expensive hour of a classic car is the one in which it is stored incorrectly. The second most expensive: the one in which someone thinks it will be fine.
We store up to 35 vehicles in our climate-controlled depot in Schwieberdingen, with care contracts and season-start check. Reserve a spot through March 2027? Quote within 24 hours.
Frachtanfrage stellen
Author
Jutta Planitzer
Geschaeftsfuehrerin Classic Car Service · seit 1991
