Energy efficient buildings

Modern construction and high quality low-energy homes

Consultancy, planning, design and construction of energy efficient buildings. It is of particular importance to emphasize that low-energy buildings are constructed with a robust solid reinforced concrete structure, they are not prefabricated or temporary structures. At the end, the customer receives a building with guaranteed indoor climate quality and low energy consumption without worrying about the details. Anyone decided to work with us will get a clear idea about the cost of the desired building and will be able to benefit from solutions best suited to his / her preferences, ideas and budget.

The differences between energy-efficient and ordinary buildings are sometimes inconspicuous to non-specialists and often building owners learn about them only when it turns out that the expenses for heating/cooling are too high and the quality of the indoor climate is unsatisfactory. Expenses for heating and cooling of a low-energy home is 5 to 10 times lower than the same of a standard building built according to the Bulgarian legislation. The difference is drastic and ends the high bills. Such an investment is strategic and increases its value over time. In less than 6 years you can payback the extra costs and if you take into account the possibility that the price of the energy carriers will increase, it will hardly decrease, the investments will return even faster.

Investment consulting

Expert opinion on high energy efficiency

In order to achieve optimal results, it is necessary to consider the energy efficiency measures before the building design is complete and construction begins. Both the specific wishes of the client and the technical and economic opportunities for their realization must be taken into account. When details are known, thanks to specialized engineering software for energy design, we are able to plan the implementation of optimal energy efficiency solutions. We can give our professional oppinion at every stage of the design process, but it is important to know that the sooner we do it, the better results could be.

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Optimal comfort

A number of solutions for a better quality of life at home

When building is not designed to provide good indoor quality, one would use the nesessary measures to achive it, which often results to much more energy consumption than if the good indoor quality was among the priorities during the design stage of the building . For having good indoor air quality, the following parameters should be within certain limits: operative temperature, CO2, humidity, day light, air age.

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Effective use of energy

Active systems, passive measures and technologies for better comfort

High energy efficiency and good indoor climate are related to effective use of existing environmental conditions and construction technologies which provide maximum comfort at low energy costs. Such a rational use of energy can be achieved by analyzing and combining together systems and architecture of a building. For this purpose, we use computational software for energy simulations.

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Renewable energy sources

Using free energy from nature

Predicting the benefits of renewable energy sources leads to a significant reduction in operating costs and is a mean of protecting the environment and preserving the exhaustible natural resources. When the building has a smaller footprint on nature, it is often called "sustainable" or "green". The main renewable sources are solar energy and geothermal energy. They can be used thanks to modern solar installations and heat pump systems.

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Low-energy homes Quality and energy efficiency

Expenses for heating and cooling of a low-energy home are 5 to 10 times lower compared to standard building built according to the Bulgarian building legislation. The difference is drastic and ends the high bills. Such an investment is strategic and increases its value over time. Within less than 6 years, you can payback the extra cost.

After 2020, any building that is not low-energy building will prove to be a bad investment. The National Plan for nearly zero-energy buildings enters into force in 2018. According to Energy Efficiency Act these buildings should fulfill several conditions: their energy consumption corresponds to Class A.; not less than 55% of the energy consumed is provided from renewable sources located on site. The aim of Directive 2010/31/EU on the energy performance of buildings is to reduce total energy consumption in the EU by 20% by 2020.

  • 45 kWh
  • 0.3 €/m²

Passive houses

A higher standard in low-energy construction works

The passive house has extremely high energy efficiency and provides comfortable indoor conditions throughout the year. The concept of its creation is based on low heat losses in a building without traditional heating systems and without active cooling.

Low heat costs make it cost effective if one considers the lifetime cost of the building. It must have a high level of thermal insulation, a minimum of thermal bridges and low infiltration, for which it passively uses the solar heat and internal storage heat inflows, as well as the recycling of the exhaust air heat. Renewable energy sources are prioritized and compared to current standards, energy consumption from non-renewable energy sources is extremely low.

The consumption in numbers

Saved heat energy is 75-90%

Annually, for primary energy for heating, cooling and ventilation, electrical appliances and lighting, the use of 120 KWH/m2, regardless of the energy source, must not be exceeded.

A building built by the standards for a passive house saves heating energy by 75 to 90%, compared to non-passive buildings.

Usually, the return on investment period for the cost of the passive systems is less than 10 years.

Life in a passive house

No special habitation requirements

Passive houses can be designed and built for anyone. The construction is based on simple materials with good characteristics, structures and building installations that meet the requirements for the passive standard. "CITY-EURO" seeks to attract investors who are looking for contractors, qualified for such projects. The company is developing an affinity for the construction of passive houses, as this is the professional future of construction building as a whole. Our country already has good design teams, a developed market for materials and equipment and most of all - informed, environmentally responsible and innovative users of passive houses, who want to invest in and keep up with the global "green" trends.

Main benefits of passive housees Comfort, costs and environmental impact

  • High thermal comfort and excellent air quality

    High thermal comfort includes conditions such as constant temperature in all rooms and equal temperature in every part of the room. Excellent air quality is independent of external conditions such as climate, air pollution, noise.

  • Green and sustainable construction

    Both as natural resources used in the input materials and in the long term - as environmental footprint, its quality impact is at a whole different level from the traditional one.

  • Consistently low energy consumption

    Total consumption is calculated based on the entire life cycle of the building.

  • Reliable and long-term technical solutions

    ...that do not require complex and expensive maintenance.

Indoor climate quality guarantee

Proven indoor environment quality

The quality of the indoor climate is guaranteed by using excellent insulation and heating, cooling and ventilation systems. Important factors are providing a constant temperature, the elimination of reheating or re-cooling of rooms, as well as the extraction of odors. According to Bulgarian regulations, there are no requirements for natural light in premises, СО2 levels, humidity and air changes. Buildings are being designed and built without the indoor air quality to be taken into account at all. We often do not feel that we are exposed to adverse impacts due to a bad indoor climate. A sign of such exposion is the appearance of molds in rooms and bathrooms which have a negative impact on health. Some of the typical symptoms can lead to chronic respiratory problems and allergies! You can read more about indoor climate quality on Optimal comfort.

Price comparison

Heating costs at low and standard energy consumption

To get a better idea of how much cheaper a home heating can be, when designed and built in a way that prioritises low energy consumption and indoor climate quality, was made a comparison of three separate strategies covering thermal isolation and the way heating. The graph on the right shows the monthly heating costs of a two-storey house with an area of 350 m² located in Sofia. Three options are compared: 1st - low energy house with heating and cooling supplied by heat pump, 2nd option - standard insulated house with pellet heating (cooling is not provided and requires additional investment) and option 3 - a standard insulated house with standard electric heating (eg electric boiler with radiators, heaters, etc., which also do not provide cooling during summer). It is also important to add that among the three models, the well-insulated building provides the highest indoor climate quality and even heat distribution in all rooms throughout their area and height.

Investment payback period

What is the return on investment?

There are standards for nearly-zero energy buildings regarding doors, windows, thermal insulation, lighting and heaing/cooling and ventilation systems. Costs are approximately 30% higher than standard. The return period of investments is short - up to 6 years, and their value increases over time.