Loving your work, Davina - I always like a good (or even a bad) pun on a Friday morning!
Great question - and it's one I can only answer by asking you a few in return:
Building Control at Belfast City Council define a conservatory thus:
"An attached structure with door access to a building and with at least two thirds of the roof and half of the walls made from translucent material (that is, they let in light)."
If your planned structure has glazed walls and a solid (ie non-translucent) roof, then, my friend, you are building a sun lounge which is classified as an extension to a property and you will need to apply to building control for approval. Some conservatories are exempt (see below) but a sunroom is always subject to building control regulations.
Another cert for needing permission is an open plan conservatory - if your new structure opens straight into a kitchen or another room with no door separating the two, then you will need to apply for building regulations approval.
There are certain things that would exempt your conservatory from being subject to building regulations. You won't have to apply for approval if:
Although some small extensions are exempt from building control, sometimes you'll find you still need to apply for planning permission, and it's less easy to give you an easy tick list of all those ifs ands and buts. Visit belfastcity.gov.uk/planning or give the Planning Service a buzz on 028 9050 0510.
They know their stuff and will be happy to help you navigate the system to get your little building standing proud as soon as possible!
Hopefully this has been helpful to you! If you have a question of your own or any property-related issue I can help you with, don't hesitate to get in touch - drop me a line to firstname.lastname@example.org, give me a buzz 028 9066 3106 or join the conversation over on Facebook, Twitter or Linked In - links in the top right corner of this page.