No, the majority of orangeries will not need planning permission as they will fall under permitted development. However, all additions will be required to comply with building regulations.
If your home is listed, you live in a designated area, such as a Conservation Area, or are planning a particularly large or multi-storey addition, then it is likely that you’ll need consent. The exact requirements will vary from project to project but your local authority will be able to provide further guidance on the necessary requirements and give an idea of acceptable designs. See planningportal.co.uk for more advice.
'If your project does require planning permission, there are ways to increase your chances of being accepted. Discussing your ideas informally first with your local planning officer is a good way to ensure you’re not wasting time and money. It’s also worth producing plans and photographs. Do your research; look for similar extensions in your area to build your case, and emphasise the build quality to make it more difficult to say no to,' says Karen Bell from David Salisbury. 'You may also want to consider telling your neighbours in advance - often a friendly and courteous heads up is enough to stop someone objecting, which gives you one less hurdle to overcome.'