Fully glazed and enclosed, without the cost or the disruption of a build. Sliding walls that open the whole side in summer and close it again in October.
Frameless or slim-framed panels that stack to one side. Open, it behaves like a pergola. Closed, it is a room.
An insulated sandwich panel instead of glass, over part or all of the roof. Keeps heat in through winter and glare out in July.
With power, lighting and a heater it works as a room from February to November. Most people run a single electric panel heater and leave it at that.
A survey is free, takes about half an hour and puts you under no obligation.