The air in a closed up RV will contain varying amounts of moisture, depending upon the local climate and the storage methods utilized. If you are able to connect to shore power, during the storage period, an electric dehumidifier is a very good safeguard against a high humidity condition. Otherwise, one or better yet, two, DriziAire dehumidifiers is advised. Open a roof vent or two, if you can, to allow moist air to escape.
To Tarp or Not to Tarp
As a concerned RV Technician, I am totally against the tarping of an RV. If your roof is maintained and in good condition, it will withstand the forces of Mother Nature.
If you simply must “tarp” your unit, build an “A” frame type of structure to repel rain or snow while allowing air to circulate beneath the tarp and above the roof of the RV. A tarp laid on the roof and draped down the walls, is an invitation to dry rot – you want the moisture to escape – not to be held in, as a tarp will do. Also, a tarp will move with the wind, regardless of how well it is secured. This results in chaffing of the sidewall paint, and we don’t want to discuss that in this article!
Clean and remove your battery(s) and store in a cool place. Top up the water level and check/recharge them monthly. Deep cycle batteries will self-discharge in a month and a discharged battery is not a happy battery. Use only distilled water to top off the water level in the cells. An uncharged battery will freeze in sub-zero weather if left outdoors.