Conservatory or extension??

sunshinetours

What way does the conservatory face and how much direct sun will it get?
I doubt if any glass roof will ever perform as well as a traditional pitched tiled roof. If you want more light consider skylights and maybe some high level windows on the two brick wall sides.

New glass technology is undoubtedly much better than it was, but it is still a compromise of heat vs light

If you really want a conservatory feel then get a conservatory but accept your heating bills will be higher

Cost wise it can end up cheaper with a traditional brick extension once you have specced your glass roof up so much that it performs nearly as well as a tiled roof