Conservatory Ventilation And Design Basics
A classic impression of conservatories is that they are hot in the summer, cold in the winter and useful only for a few weeks a year.This understandable impression is due mainly to conservatory proportions that are based on the original Victorian designs and styles.
Unfortunately, the early Victorian glass houses were applied to country houses and manors as glass was so expensive. This meant that the structures were very tall, at least two floors high. This gave them an advantage for ventilation as they had enough height to let the chimney effect work to draw hot air up and cool air down. (The principles of the chimney effect are that a chimney only works if there are apertures at a high level, and openings at a low level to let air circulate. the higher a chimney is, the better it works, so Victorian conservatories ventilated well because they were and still are tall.
Unfortunately modern conservatories are applied onto much shorter buildings and as such have difficulty ventilating. It is easy to see how all glasshouses can ventilate effectively, all you have to do is look at commercial greenhouses. If they didn’t ventilate properly they would be out of business. a commercial greenhouse has a large opening at a high level and also at a low level (usually about 20-25% openings). If you therefore look at modern structures with small openings on the roof, and no openings at a lower level you can immediately see why they have difficulty ventilating at all.
From the point of view of manufacturers, the status quo seems to be sufficient for them to continue with what they are used to. Also there are problems with leaks if you use a good double glazed panel on the roof if you have to keep opening it up and closing it down. It’s not only heavy but also a delicate piece of glass, this leads to leaks from the glass units slipping and failed double or triple glazing.
The solution as I see it is to use a forced system of ventilation to push and/or pull more air through smaller apertures. The system that we use here is to have a twin ridged structure with a fan in the aperture that is left. This allows ventilation to go through the framework of the structure rather than have moving glass panels. This has the added advantage of enabling ventilation whilst all the windows and doors are locked and the structure is secure (as long as there is sufficient trickle ventilation at a low level).
Using this approach gives a couple of other advantages that is also worth noting. Firstly, as the glass is fixed in place, larger better insulated pieces can be used allowing for a better overall insulation value for the structure. Secondly fixed units allow you to use more robust gasketing between the frame and the glass allowing for not only a watertight, but also an airtight structure making heating and maintaining temperatures easier.
Heating;
Heating a glass structure is different from heating a solid walled room because the temperature is more prone to fluctuating from hot to cold depending on how much of the sun is directly hitting the conservatory. Underfloor heating is ideal for this if it can be run as its own zone. The solid flooring used with underfloor heating is also good because it can get heated by the sun whenever possible to give you free heating for the structure. In fact, if you can use a large mass insulated into the foundation then the floor can act as a kind of storage heater locking away the free heat that the structure gains over the course of the day, giving it off in the evening. conservatory roof panels