Orangery, conservatory or extension?
They look similar from the garden but live very differently. How to choose between the three.
People often ask for a conservatory and end up with an orangery, or ask for an orangery and realise an extension suits them better. The difference is mostly about how much glass there is and how the room feels in January.
Conservatory
Mostly glass, including the roof, on a low brick wall. The cheapest of the three and usually permitted development. The drawback is temperature: too hot in summer, too cold in winter, so many end up as a room for the dog's bed. Modern glass helps but does not fix it.
Orangery
Solid brick piers and walls, a flat insulated roof with a glazed lantern in the middle, and large glazed doors. It is warm all year and feels like part of the house. It costs more than a conservatory and roughly the same as a simple extension. Planning rules are the same as for an extension.
Extension
A proper room with a conventional roof and as much or as little glazing as you want. The most flexible option and the one that adds most value, especially as a kitchen-diner. Rooflights and bi-fold doors give you much of the light of an orangery.
Our view
If you want a garden room you will use every day, an orangery or extension is worth the extra over a conservatory. Between those two, choose an orangery for the look and the light from above, an extension if you want to move the kitchen or need a wider space.