Orangeries date back to 1545 where the first recorded one was built in Padua, Italy. Initially they were sparse, practical and not ornate but were later developed to be exotic greenhouses for large country houses.
In recent years they have become very popular, where their solid construction is seen as a the middle ground between an all glass conservatory and a normal extension to someone's home. This begs the question, what exactly are they and how are they different from conservatories.
The first difference you will notice is the roof. Conservatories are all glass while orangeries have lantern roofs. Lantern roofs are best described as a normal flat roof but with a middle section that contains a large pitch glass roof. In car terms, it’s a building with raised and interesting ‘sun roof’. This of course opens the room out by adding light and detail that you cannot achieve with a normal extension. It also adds the feeling of solidity, and it is a sort of feeling that you do not get with a conservatory because it’s roof is just all glass.
This solidity is enhanced by the building materials too. Traditional orangeries have masonry walls built up a few feet (one metre) and then have glass extending up to the roof. So they are very open and light, but in essence look and feel more like a masonry building. Along with the feeling of rigidity, the solid design also helps keep the look and design consistent with the original building because it is usual for the masonry to match that of the house.
As contemporary designs have influenced the world of architecture, so to have they influence the design of orangeries. Recently, more and more orangeries have been built in hardwood. So where the masonry wall forms the basis to the traditional orangery, a hardwood wall forms the basis to a more contemporary look. This transforms the building quite a bit - it is a different material with a different look and feel. These designs often contain a greater amount of glass as a proportion of the wall, so again this changes the feel of the building making it appear more open and more contemporary.
All of these design decisions depend upon a few key factors, the original building, the design you want and the lifestyle you want within your new building. A large traditional house with a traditional orangery fits well, while a contemporary building often needs more glass to look compatible. If this was a scale, with a building at one end and a greenhouse at the other, an orangery is closer to the building while a conservatory is closer to the greenhouse (although that analogy does cheapen a greenhouse too much). So thinking of lifestyle, if your orangery is next to or forms part of your kitchen-diner, it really feels part of the house. If this is where you are going to spend most of your time or how you want to use the space, choosing an orangery would be a good decision.