The "indoor or outdoor?" question is one of the first you face when looking at storage options for a caravan or motorhome. The instinctive answer is "indoor must be better" — it is, on the surface, more protective. But the reality is more nuanced. Each option has genuine strengths and genuine drawbacks, and the right choice depends on your vehicle, your usage pattern and your local climate.
What "Indoor Storage" Actually Means
Indoor storage in a UK leisure-vehicle context usually means one of:
- Heated, climate-controlled buildings (rare in the UK, expensive)
- Unheated barns or sheds (more common, especially on farm sites)
- Purpose-built leisure-vehicle storage barns (offered by some larger sites)
The protective value of indoor storage depends heavily on which of these you actually get. A modern, dry, ventilated barn is genuinely excellent. An old farm shed with a leaky roof can be worse than a well-drained outdoor pitch.
What "Outdoor Storage" Actually Means
Outdoor storage in this context normally means:
- Hard-standing pitches on a secure compound (the most common form)
- Grass pitches (still occasionally found, generally avoid in UK winters)
- Covered pitches (a halfway house — outdoor pitch with a canopy roof)
The vast majority of UK leisure-vehicle storage is hard-standing outdoor on a secure site, because it suits the vast majority of vehicles and owners. It is the default, and it is fine for most people.
Where Indoor Storage Wins
Genuinely sheltered indoor storage protects against:
- UV degradation of paintwork, seals and plastics
- Frost on water systems (less of an issue if you drain down properly anyway)
- Standing rain on roofs and seals
- Hail damage (rare but expensive)
- Tree sap and bird mess
For premium motorhomes and high-value caravans, particularly those with delicate paintwork or extensive plastic mouldings, indoor storage can extend the cosmetic life meaningfully over a decade.
Where Outdoor Storage Wins
Hard-standing outdoor on a properly run site has its own advantages:
- Lower cost — typically significantly cheaper than indoor for the same security level
- Easier in-out access — no lining-up to manoeuvre between barn columns
- Better airflow — counterintuitively, many indoor stores have humidity problems because air does not circulate. Outdoor pitches do not get damp the way a poorly ventilated indoor space can.
- More forgiving of large vehicles — A-class motorhomes especially can struggle to fit indoor spaces
The Damp Question
This one surprises people. The conventional wisdom is "indoor is drier." In practice it depends entirely on the building.
A well-built modern storage barn with proper ventilation (ridge vents, soffit gaps, sometimes powered air movement) keeps humidity low and is genuinely drier than outdoor.
A converted agricultural building, sealed up to keep weather out but with no ventilation thought, can become a humidity trap. The vehicle inside is constantly exposed to higher humidity than the outside air. Damp ingress accelerates rather than slows.
If you are evaluating an indoor storage option, ask about ventilation directly. "Ridge vents and soffit gaps" is the answer you want to hear.
What This Means in Practice
For most touring caravans and standard motorhomes used regularly, hard-standing outdoor on a secure compound is genuinely fine. Modern leisure vehicles are designed for outdoor use and outdoor storage. The added cost of indoor storage is rarely repaid in vehicle longevity for everyday vehicles.
For high-value motorhomes (£100,000+), classic caravans, vehicles with show paintwork, or vehicles you only use a few weeks a year, the case for proper (well-ventilated) indoor storage gets stronger.
For trailers, the calculation is different again — most trailers tolerate outdoor storage indefinitely. Boats and PWCs follow their own logic, mostly driven by trailer storage convenience.
The Hybrid: Covered Outdoor
A small number of sites offer "covered outdoor" — a hard-standing pitch with a canopy or carport-style roof but open sides. This gets you most of the benefit of indoor (UV, rain, hail) without the humidity downside. If your local site offers it, it is often the best compromise.
What to Ask a Site
Whether the site is indoor or outdoor, the questions are largely the same:
- What is the surface (hard-standing? level? drained?)
- How is the security set up?
- Is the site CaSSOA rated, and at what level?
- For indoor: how is ventilation handled? What is the floor surface?
- For outdoor: is there shelter from prevailing winds and overhanging trees?
A good site is happy to walk you through the answers; a poor one will gloss over the details.
Final Thought
Do not assume indoor is automatically better. Look at the specific site, the specific building or pitch, and the specific match to your vehicle. For the average UK caravan or motorhome owner, a well-run hard-standing outdoor pitch on a secure CaSSOA-rated compound is often the best practical answer — well-protected, well-priced and easy to use.