Choosing the correct size protective cover for your caravan is easy. To measure your caravan for a cover, simply measure the caravan body, measuring parallel to the ground, from the rearmost point to the foremost point, including the gas locker but NOT including the A-frame.
Caravan Cover Sizing
See the diagram above for a guide. Caravan Covers are measured purely by length - they are not measured for height.
Where your caravan is just below a step in sizing (i.e. your caravan is 13' 11" and the size step is at 14", choose the smaller size. If you choose the larger size the cover will be much more difficult to fit as the excess material will need firmly strapping up to prevent flapping and possible tearing in heavy winds. However allowance should be made for particularly large satellite dishes that are permanently mounted to the caravan roof.
Motorhome & Campervan Cover Sizing
The same principles apply to measuring up for a full size Motorhome Cover. Measure parallel to the ground from the front to rear of the motorhome.