Simply clip these smart insulation panels over the greenhouse glass, using the existing glass fastening system. See our Features and Appraisals pages for more information on - Insulite Panels.

Should I insulate my greenhouse?

A greenhouse gives discerning gardeners many advantages in their battle with the elements. A greenhouse will offer protection against wind and rain, and when shaded it will protect plants from leaf scorch. Humidity and water usage can also be controlled when growing plants under glass.

Cold greenhouse

Temperatures within an unheated greenhouse, however, are very much dependent on what is happening outside. This is because the interior of the greenhouse will be warmer than the temperature outside on bright and sunny days, but at night and during cloudy days the temperature inside, (wind chill aside) will be very much the same as the temperature outside. A greenhouse without some form of artificial heat source such as the one described is usually referred to as a "cold greenhouse". This type of greenhouse has limited advantages, and is used mainly to extend the growing season by promoting early growth in spring and extending the ripening period in autumn. Cold weather and severe frosts, however, will penetrate the cold greenhouse, rendering it useless for storing things such as tender plants, tubers, corms or bulbs or for the early propagation of seedlings. For this purpose some form of heat source is required

Cool greenhouse

When a heat source sufficient only to keep frosts at bay is supplied, this type of greenhouse is called a "cool greenhouse". To keep a greenhouse frost- free need not be expensive, especially if some of the following steps are taken. Try to site your greenhouse where it is sheltered from prevailing winds and where the winter sun can reach its longest side. Reduce draughts by filling in gaps with putty or similar material. A full greenhouse maintains its heat better than an empty one so where possible leave full water containers in the greenhouse so that the heat absorbed during the day can be slowly released at night. Partitioning the greenhouse so that only a small portion of the structure need be heated is another way of saving costs. Insulating the greenhouse will certainly improve results but savings where a cold or cool greenhouse is concerned would have to be worth the initial outlay.

Hot greenhouse

Much higher minimum temperatures are required if the greenhouse is to be used for all year cultivation, the growing of tender plants, or for the early propagation of bedding plants. This type of greenhouse is referred to as a "hot greenhouse". In this type of greenhouse fuel efficiency is of paramount importance, and since glass is a very poor insulator, every means of fuel saving must be considered. A thermostatically controlled heater will cut fuel bills but remember, the faster the heat disperses through the glass, the faster the heater will have to come back on to maintain the required temperature. Insulating the greenhouse can slow the rate at which heat is lost through the glass, reducing costs and helping to reduce large fluctuations in temperature.

Several types of insulation are available, but if the type you choose is made of plastic, make sure it is UV stabilised so that it doesn't start to deteriorate after just a couple of years' use. Also choose one that allows the maximum amount of light possible to enter the greenhouse as light is at a premium during the winter months. Fuel is set to become more and more expensive as governments come under greater pressure to reduce greenhouse gasses. After all it really doesn't make sense to pay good money simply to contribute to global warming.

Author - K.R.McGrath inventor of the Insulite Panels greenhouse insulation system