Five "M" and design

The house itself is designed as a three-story building, with the living space size of the basement being 50.92 m2, on the first floor 76.55 m2, and on the second floor 77.63 m2. The author of the project and also the investor of this family house is a professional architect; the construction was completed in August 2013, and a family of four has been fully utilizing it since that time.

The household uses only one type of energy for its operation - electricity. The heating of domestic hot water is provided by a Buderus unit, which includes an integrated air/water heat pump. The builder, who is also the author of the project, placed great emphasis not only on the architectural solution of the house and the design of the internal spaces but also on the design of details. The possibility of installing heating technology into the structure of the building, where the heated space is absolutely clean and free from disruptive technological elements, was very important in the choice of technology. Other important criteria for selecting the heating system were, of course, economics, lifespan, and comfort. The decision was made for large-area electric direct heating, and aside from the already mentioned design, the reasons for this choice can be summarized in the following five points:

- minimization of operating costs
- minimization or complete elimination of maintenance and service costs
- maximization of lifespan, including warranty period
- maximization of heating comfort in terms of heat perception
- minimization of investment costs

After evaluating offers on the market, the investor chose the large-area ECOFLOOR® systems. The heating technology is installed in atypical cable mats that are placed on thermal insulation below the load-bearing slab - this is a so-called partially accumulating system. The requirement for their special maintenance is zero; maintenance and service are the same as for standard domestic electrical installations.

The chosen large-area ECOFLOOR® system is characterized by the desired user comfort and uniform temperature distribution throughout the height of the room. In classic central heating, where the room is heated by a hot water radiator, heat is distributed from one source at a relatively high temperature, and warmth spreads into the space through the circulation of warm air. The room is thus warmed from the ceiling downwards, and the heat is distributed unevenly. This principle is characteristic of all convection systems - electric direct convectors included.

Because heating is about feelings, we feel comfortable in a heated space only when the required temperature is also reached at the floor level, as we perceive heat most sensitively there. In convection systems, however, it is warmest in the area where warmth is not needed at all - that is, at the ceiling. To achieve the desired comfortable temperature at the floor level, it is necessary to "overheat" the room, which is undesirable from at least an economic perspective.
Large-area heating systems (both floor and ceiling) completely eliminate this disadvantage, as they ensure a uniform temperature distribution in both the horizontal and vertical planes of the room - this guarantees not only high user comfort but also low operating costs.  

Underfloor heating, which is very pleasant especially with cold floor coverings such as tiles, laminate flooring, etc., is now quite commonly used and is particularly standard in bathrooms. The ECOFLOOR® program offers a wide range of product groups and constitutes the most extensive offer on the market. The difference compared to hot water underfloor heating is primarily in the very low investment cost for technology and implementation. This was also one of the main reasons for choosing electricity as the main heat source.

A significant influence on heating operating costs is the choice of regulation. The market offers a large number of thermostats of various designs, versions, and price ranges, but usually, these are classic thermostats that no longer meet the requirements for savings in operating costs - heating control occurs only in on/off mode. Therefore, the choice fell on the central regulation system BMR RT-64 with pulse power control. This is a regulation where all programming (temperature and time) is done on a single central control unit via PC, and if the unit is connected to a local computer network (router), it can also be operated remotely via a tablet, smartphone, or laptop. The heating output is switched using power semiconductors - that is, contactless and completely silently, and in individual rooms, there are only temperature sensors. The design of room sensors can be adapted to other switches and sockets or can be integrated into common frames. BMR regulation, thanks to pulse power control and high precision in maintaining the set temperature, is characterized by up to 30% savings in energy consumption compared to standard room thermostats.

The heat loss of the building is 4.7 kW, and the acquisition costs for the ECOFLOOR system and central regulation amounted to approximately 87,000 CZK (excluding VAT). The operating costs for heating will be monitored over the long term - in addition to the main electricity meter installed by the electricity supplier, a subsidiary meter is also installed in the house for measuring electricity consumption for heating the building. It is very likely that, in line with the long-standing experience of other energy-efficient new homes monitored by FENIX Jeseník, the electric underfloor heating in the family house in Plzeň will be very economically advantageous. More information can be found at www.fenixgroup.cz.