No worries - I'm not sure the distinction between a log cabin and a lodge is valid - what IS the difference?. The key thing is that the lodge (or log cabin or caravan) remains potentially mobile (I think having wheels is a a key part of the definition for some reason, even though they are all moved on flat bed trucks and with cranes) and is on a holiday park (not a residential one).
It can then be treated as plant and equipment for the purposes of capital allowances
http://www.hmrc.gov.uk/manuals/camanual/ca22100.htm
"Accept that a caravan, which is provided mainly for holiday lettings
on a holiday caravan site, is plant whether it is moved or not. Caravans
occupying residential sites do not qualify for capital allowances. As
far as a holiday caravan site is concerned, treat anything that is
treated as a caravan for the purposes of:
- the Caravan Sites and Control of Development Act 1960 (c. 62) (CSCDA), or
- the Caravans Act (Northern Ireland) 1963 (c. 17 (N.I.)),
as a caravan. Those acts give caravan a wider meaning than its normal
one. In them, caravan covers double units delivered in two sections and
then joined together and wooden lodges provided these are moveable. But
it does not cover structures that are not moveable, even if these are
otherwise identical."