Hi,
I'm a Planning Consultant (a nice one;)) in England and Wales the Prior Notiication procedure is a process where you submit details of the location, scale and proposed use of the building. If the proposal meets certain criteria and is classed as Permitted Development (i.e. something that does not require planning permission) the Authority has 28 days from notification of reciept of your submission to then tell you (a) whether it is not classed as permitted development and planning permission is required or (b) to comment on its general appearance. colour etc. but not its principle. Whether something is permitted development or not depends on a whole range of things such as the size of the enclsoure you are putting the building, the size of your holding, the use of the building, proximity to roads, houses, listed buildings, aerodromes .. there's quite a list, so let me have some more details and I'll see if I can give you some more advice.
FarmerJase