Storing an RV Here Is a UV Problem, Not a Freeze Problem

Most RV storage checklists are written for climates where the problem is water freezing and expanding. Winterising, antifreeze in the lines, blowing out the plumbing.

Here, that is mostly beside the point. Yorba Linda gets a handful of nights near freezing in a hard year. What we get instead is relentless ultraviolet exposure and heat cycling, and those damage a stored coach far more than a mild winter does.

What actually degrades while a coach sits

Sealant. Direct UV exposure on roof sealant is the fastest degradation path there is. A coach stored outdoors in full sun for eight months loses more sealant life than one driven the same period in shade. Nothing about being parked protects it.

Gelcoat. Oxidises and chalks under UV. Recoverable by paint correction at $850 to $6,500 up to a point, then not.

Rubber. Every seal, hose, awning and tyre. Rubber under UV hardens and cracks, and hard rubber does not seal.

Interior finishes. Sun through windows fades upholstery, cracks dashboards and degrades laminates. Uncovered windows in a stored coach cause real damage over a season.

Batteries. Heat is worse for battery life than cold. A coach stored in summer heat with batteries in it loses capacity faster than one stored in a cold garage.

The compression set problem

This one catches destination and long stay owners specifically and it is the most expensive item on the list.

A slide seal held compressed for months takes a permanent set. The rubber stops springing back. When the slide is finally retracted, or the coach finally moves, the seal no longer conforms and it leaks.

Same for awning fabric held rolled in one position, and for door seals.

The fix is not complicated: cycle things. Extend and retract slides monthly if you can, and if the coach is going to sit extended for a season, understand that the seals are on a clock and budget $400 to $3,000 for a seal set when it moves again.

What to actually do before a coach sits

In order of value.

1. Cover it, or park it under cover. By a wide margin the highest value action. Everything above is a UV problem and shade solves most of it. A quality fitted cover beats a tarp, which traps moisture and abrades the finish.

2. Reseal anything marginal first. Do not store a coach with sealant you know is failing. Eight months of sun on a marginal bead finishes it, and then you have water sitting in a wall for months with nobody looking. Recoat and reseal runs $750 to $4,500.

3. Cover interior glass. Reflective covers or interior blinds fully closed. Prevents upholstery and dash damage that is expensive and largely irreversible.

4. Address the roof, properly. Not a wash. An inspection of every penetration and every seam, done before storage rather than after.

5. Cycle slides and awnings monthly. If you cannot, retract them and accept the seal clock.

6. Batteries out or on a maintainer, in shade. Heat plus discharge is what kills them.

7. Tyres covered and pressure checked. UV cracks sidewalls, and a tyre with cracked sidewalls is not safe regardless of tread.

8. Plumbing drained. Not for freeze, for stagnation. Standing water in a fresh tank for eight months in heat is a biological problem.

What not to bother with

Antifreeze in the lines, unless you are storing at elevation. Drained is sufficient here.

Elaborate rodent proofing, which is genuinely climate dependent and less of an issue in most Orange County storage facilities than in rural storage. Still worth a look at any opening, but it is not the first priority some checklists make it.

What to check when it comes out

Before you drive it anywhere:

• Every seal you cycled, and every one you did not
• Roof penetrations, because eight months has happened to them
• Tyre sidewalls for UV cracking
• Slide operation, listening for anything different, and ideally current draw
• Interior for any staining that appeared while nobody was looking
• Water test if you have any doubt at all about the roof

Finding a wall gone soft after storage is common, and it is almost always a sealant failure that existed before storage and got eight uninterrupted months to work.

Which is the whole argument for item two on the list above. The cheapest thing you can do for a coach that is about to sit is fix the roof first.