I have had a full-time job with my current employer for about sixteen years. The core part of the job is routine and doesn't fill the hours, but there are opportunities to do other stuff too, which I enjoy because it overlaps with my hobby.
Both the office and my house are fine for doing the core part of my job, and I usually work about half the time in each. However, the additional work would really benefit from specialist facilities which aren't available either at the office or at home. So, I'd like to rent a workspace in another building. I could use this both to work in and for my hobby (I own all the necessary equipment myself, I just need somewhere suitable to put it).
I think it's unlikely my employers would contribute directly to the rent, but are there any tax breaks I could take advantage of in renting a workspace, or do I just have to pay the rent myself out of my net income? I want to remain in full-time employment rather than going freelance or contracting.