Compared to STEP® flat heating elements, electric cables need 2.5 times more power and water tubing (1/2″) need 2.08 times more power to heat the same floor surface area.
Radiant Floor Heating with a Flat Heater is more Efficient
According to a recent study STEP Warmfloor® was measured to be significantly more efficient than other heating systems. Francesco Schiavone, PhD, (PhD, BEng (Mech) – University of Florence, Italy, Senior Research Associate – Royal Melbourne Institute of Technology, Australia) compared the heat transmission from STEP Warmfloor® self‐regulating heating element with electric cable systems and water tubing systems.
His key findings was:
- To give the same heat output, an Electric Cable system would require 2.5 times more wattage
- To give the same heat output, a water tubing system (Hydronic) would require 2.08 times more wattage
How is this possible? “Watts are watts and give the same heat output.”
There is no discussion that an equal amount of wattage will generate the same energy output. So how can Francesco Schiavone claim that STEP Warmfloor® flat heating elements require less wattage to heat a floor? Is it to fantastic too be true?
Let us take an example from the kitchen that most people are familiar with; You want to boil 10 cups of water in a large pot using 1000 watts.
First you place the pot (A) on a large cooking plate, which has the same diameter as the pot. Then you place an identical pot (B), but on a smaller cooking plate. In which pot will the water boil faster?
As most of us have experienced, the stock pot (A) on the larger cooking plate will have the fastest boiling water with the same amount of energy.
It is all about distribution and transmission of heat. If you compare the surface area of a cable or water tubing with STEP Warmfloor®’s flat heating element it is similar to the different sizes of cooking plates. While cables and tubing only cover a fraction of the floor, an installation of STEP Warmfloor® flat heating element will cover more than 60% of the surface.
The challenge lies in changing the thought process from an efficient component to an efficient system. To have an efficient heating system, it is not sufficient that the heating product is good, it is as important that the heat distribution is designed properly.
For efficiency, it will also be necessary to take into consideration the location and type of construction, including thermal insulation and floor covering installed.
When Francesco Schiavone made his calculations he based it on Newton’s law. According to Newton’s law, the rate of heat transfer to the surrounding air is proportional to the floor exposed area and to the difference between the floor temperature and the air temperature.
Watt is still Watt, but when it comes to radiant heating of a house STEP Warmfloor™ is more efficient than cables and water tubing.