Conservatories have become a popular additions to many homes in the UK. The growth of the market has been coupled with a rise in the expectations of homeowners and many conservatories are now required to be used as an all year round room. With modern materials and careful planning this is achievable, however many conservatories fall short on both counts leaving householders with rooms that are too hot in the summer and too cold in the winter.
If one ignores concerns over energy usage and the associated costs to the planet and bank balance, it is possible to heat even the most poorly insulated conservatory. However, it is far better financially and environmentally to improve the insulation at the design and construction stage.
Walls with 75 to100mm cavities have become the norm elsewhere in the building industry and this standard should be met on conservatories. Floor insulation should also be of the same thickness and placed as close to the floor surface as possible, in most circumstances this means beneath the screed.
Low emissivity (low-e) glass has been widely available for many years, a coating on the inner pane acts to reflect heat back into the room. This is typically known as either “soft coat” or “hard coat” the former being better and more expensive, the later cheaper and offering less insulation. Double glazed units made using glass with a soft coating can achieve a u-value as low as 1.1W/m²K. This should be used where ever possible to conserve energy and keep the room comfortably warm.
The other issue is overheating, potentially a harder problem to deal with. It is easy to misjudge the effects of the sun when planning a conservatory in poor weather. Even observing the light from the sun on the ground where the conservatory is to be built can give a false impression if the sun is not directly overhead.
It is far better to keep the heat out than attempt to cool the conservatory down. Air conditioning units are relatively inexpensive to install, but are costly to run, potentially noisy and not the most ecological use of resources.
Improvements in glass technology have worked their way down to the domestic market. It is now usual for some firms to install glass which reflects up to 75% of the sun’s heat. This means that very little solar heating occurs even in conservatories that are fully south facing. This solar control glass will often have a slight tint which will also block out a degree of visible light. Any concerns that this will make the conservatory to dark should be dismissed; if the roof is glazed there will be more than enough light!
Proper ventilation is the next most important factor, ideally openings high up in the roof and low down in the side windows. Automated roof vents will be more effective than manually operated ones by virtue of the fact they will be opened at the correct times.
A reputable supplier should be able to give specific advice for individual locations and buildings, but the overriding principles are to keep any heat you generate in and keep most of the heat from the sun out.