It isn't the material that drives the PP need - its where you live, its size and where you want to put it in relationship to other things around (including Highways and neighbours). See here and post again if you need more help.
http://www.planningportal.gov.uk/england/genpu b/en/1106655490418.html
This applies in England; under devolved Government Scotland and NI do things differently, and Wales seems to be currently making up its own new rules (but don't expect too much different from England).
Also don't underestimate the energy and effort required to put one of these things up - including foundations and transporting it in its sections.