When hot, moist air comes into contact with colder surfaces, condensation occurs Condensation is much more common in conservatories than Orangeries because the latter usually have solid roofs, which can help keep the temperature consistent within the building. Also, the abundance of windows in a conservatory vastly outnumbers that within an Orangery. As a result, condensation can be very severe and widespread, and there have to be greater efforts taken in equalising temperature. The best way to handle condensation within a conservatory is to improve ventilation. There are simple ways to do this, like leaving doors or windows open. Alternatively, you can have vents and extractor fans installed. Alternatively, you can add more insulation to the building. For example, double or triple glazing. This will keep the building cooler during summer, and hotter during the summer. You could always entirely kill the moisture in the air by having a dehumidifier. This will pull in the moisture from the air and fill a tank with it. Of course, these humidifiers run on power and will have to be emptied regularly. Conservatories in Scotland are often built with additional insulation options to account for the colder weather.