Wall heating or underfloor heating?

At first, the trend towards underfloor heating started a few decades ago. In recent years, this has been replaced by a rising popularity of wall heating. For many homeowners, this raises the question for different reasons, whether better a wall heating or underfloor heating.

Convection heat vs radiant heat

For heating, a distinction must be made between two heating techniques: heaters that use convective heat and those that use the principle of radiant heat. In convection heating, the room air is heated. In radiant heat, however, the body or object that is illuminated.

The classic example is the open campfire, which warms even in freezing cold, as it illuminates the body. Although the ambient air heats only marginally, humans feel it as pleasantly warm. This is reflected in the radiant heat also in energy costs.

Energy saving potential due to radiant heat

In order to heat up the room air in a room above 18 degrees Celsius, the additional energy required for every degree of increased heat increases by six to seven percent. For example, a room where radiant heat is heated only heats up to 18 degrees. The radiant heat leads to a perceived room air heat of 21 degrees.

Wall heating or underfloor heating

A heating system that uses this principle very successfully is underfloor heating. However, lateral radiant heat is perceived as more comfortable. The wall heating is the functional principle nothing more than a vertical floor heating. In principle, therefore, the greater sense of comfort speaks for a wall heating instead of underfloor heating.

Functional principle and physical procedure for wall heating

However, the wall heating requires conditions from which their disadvantages arise. Thus, the wall heater must preferably be mounted in the outer wall. The air in the area of ​​the wall heating heats up, creating a "suction" to the coldest wall. Here the air falls off as it continues to cool. Arrived at the bottom, the air is now again sucked towards the wall with wall heating.

Is the coldest wall the outer wall, because the wall heating is located on an inner wall. Is the cooling of a poorly insulated exterior wall particularly high. This results in a permanent cool train on the feet. If the coolest wall is an interior wall, it is only marginally cooler than the room air and this effect weakens significantly.

Insulation to the outside and required area

At the same time, however, the outer wall behind the wall heating must be very well insulated, as otherwise much heat is radiated to the outside and wasted. Especially the wall heating in the old building without insulation is therefore problematic.

The wall heating is not always preferable to underfloor heating

In addition, the wall heating requires the largest possible area. This is further restricted by windows. In rooms mounted on interior walls, the heating power is severely limited by furniture placed in front of it. In addition, the hammering of nails and drilling holes for dowels is an enormous risk. Only if all conditions for the use of a wall heating were created, this should be preferred to the floor heating.

Tips & Tricks

Another possibility would be the combined use of underfloor heating and wall heating. However, the insulation of a building should always be optimized to such an extent that there are no restrictions due to significant energy loss.

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Video Board: Plastered Wall Heating/Cooling