conservatory conversion

Need a downstairs toilet, only option is to convert conservatory.Problem is how to make the most of the space.Conservatory size is 4.978m long x 3.15m wide (outside measurement )I don't want to demolish part of conservatory to just have a toilet, I would like to utilise it all or add on. Footings are a metre deep and drains are right next to the conservatory by to the hosepipe.I am open to ideas