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This section calculates the Power required to heat a greenhouse or conservatory structure in winter based on your input parameters.  This calculation is intended as a guide for estimation purposes only . Other factors like wind shear heat loss can also significantly increase heating requirements.

Please enter here the square feet surface area of the structure. If you do not have these calculations, please go to our Structure Surface Area Calculator further down this Page.     sqft
Please enter here the minimum outside winter night time temperature in Centigrade that you want to protect

    Min C

Please enter here the minimum inside structure temperature in Centigrade that you want to maintain during the minimum outside temperature that you entered above.     Max C
Please enter here the appropriate heat loss factor that equates to your structure from the table below.    Heat Factor
Please hit calculate - This number is the Power that you need in Watts to achieve the desired temperature uplift.  Please divide by 1000 for Kilowatts     Watts

Heat Loss Factor Parameters - Please chose the one that most represents your Structure

Single layer of glass 1.1 Double Layer polycarbonate 0.7
Glasshouse double glazed aluminium frame 0.7 Triple layer polycarbonate 0.55
Glasshouse Polythene lined 0.8 Triple polythene (bubble wrap sandwich) 0.5
Glasshouse bubble wrap lined 0.6 Single layer of polythene (i.e. polytunnel) 1.1
Conservatory Manufacturer Double Glazed 0.55 Double layer polythene (air inflated) 0.6

  Square Surface Area Calculator for a Standard Gable End Greenhouse Structure

Length of Greenhouse           "L"   Feet
Width of Greenhouse            "W"   Feet
Height of Greenhouse           "H"   Feet
Eaves Height of Greenhouse  "E"   Feet
Surface square area of your greenhouse   Sq Feet

  Square Surface Area Calculator for a Lean To Conservatory Structure

Length of Conservatory          "L"   Feet
Width of Conservatory            "W"   Feet
Height of Conservatory           "H"   Feet
Eaves Height of Conservatory  "E"   Feet
Surface square area of your conservatory   Sq Feet

  Square Surface Area Calculator for a Polytunnel

Length of Polytunnel          "L"   Feet
Width of Polytunnel           "W"   Feet
Height of Polytunnel          "H"   Feet
Hoop Length of Polytunnel  "P"   Feet
Surface square area of your polytunnel   Sq Feet

To see our Greenhouse Heater Range from Parasene and BioGreen Please Click Here