## Not over or lower installation, get the right calculation of the wattage you need

BASE VALUE : 32 WATTS/m2

At minimum 10 cm roof insulation/ insulated cavity walls/ ceiling height 2.6 meters

Room temperature 20°C/ Ambient temperature up to -15°C

Minus 20%

• Bathroom

• Conservatories (Glass)

Correction Factors

Extra 120%

Extra 30%

• Passive House

• None or little external wall insulation (old buildings)

• Poor roof insulation

• External wall >40%

• Window area 35% to 45% of external wall area.

• Wood covered floors, walls or ceilings (untreated)

• Ceiling height between 2.6-3.4 meters. (Not hallways)

• Room temperatures above 20°C

• Window area 20% to 35% external wall area.

Extra 20%

HOW TO CALCULATE THE WATTAGE YOU NEED AND GET YOUR HEATER

1). Measuring and get the room/ space size in square meter (m2)

2). Multiply the total area by the base wattage

3). Apply correction factors if necessary (plus or minus)

4). Final the wattage and choose the heating panel that covers your heat needed.

For example:

1). Room size is 3m x 3m = 9m2

2). 9m2 x 32 Watts (base per m2) = 288 Watts

3). Your room has external wall more than 40% --> (Correction factors Extra 30%--> +30%)

= 30% of 288 watts = 87 Watts

4). Your room has window 20-35% of external wall --> (Correction factors Extra 20% --> +20%)

= 20% of 288 watts = 58 Watts

So, 288+87+58 = 433 Watts = 48Watt/m2

Here, with Amberays PX470 which has a power input of 470 Watts, will be sufficient to cover the area of the room.

AVERAGE WATTAGE TO TAKE INTO ACCOUNT FOR THE HOUSE TYPE

Basically, it is recommended that you use the base value wattage and the correction factors to calculate your needed heat of the room/ house.  However, please keep in mind that the average heat your rooms may need is also according to your house type; built and insulation, so you have idea if the input power is under-install or over-install.

• Houses with very good insulation (mainly built after year 2009)  = 30-40 Watts/m2

• Houses with good insulation (built between 1995-2008)               = 40-55 Watts/m2

• Houses with poor insulation                                                              = 55-65 Watts/m2

• Houses with NO insulation                                                                 = 65-75 Watts/m2

• High halls (direct heating)                                                                  = 70-80 Watts/m2

• Bathrooms                                                                                           = 70-95 Watts/m2

• Conservatories                                                                                    = 70-95 Watts/m2

IMPORTANT

• Under-install power, results in a slow warm in the room or might not be warm at all, and that costs high energy consumption.

• Over-install power, results in a quick warm in the room, but that is considered less efficient energy consumption.

• Rooms with more than 40% outer walls or large windows will require more heat than rooms with less outer wall area and small windows.

**Please bear in mind that the calculations should be taken as a guide only and it is not a detailed heat loss calculations.**