If your second home is a static caravan, mobile home or moveable chalet, and you use TV receiving equipment there at the same time as TV receiving equipment is being used in your main licensed home, you need a separate TV Licence to cover your second home.
However, if the TV in your static caravan, mobile home or moveable chalet is never in use at the same time as the TV in your main home, you don't need a separate licence. But you do need to complete a declaration form and return it to TV Licensing.
If your second home is a boat or touring caravan or vehicle, and you use TV receiving equipment to watch or record TV there, you don't need a separate TV Licence. You will be covered by the TV Licence for your main home.
http://www.tvlicensing.co.uk/information/secon dhome.jsp