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Frequently asked questions about passive houses


What is a passive house?
- A passive house is characterized by a very high degree of thermal insulation which falls within the following standards set by the Passivhaus Institut, Darmstadt:
the average annual energy consumption for heating does not exceed 15 kWh / sqm, the annual thermal load does not exceed 10W / sqm, the average annual primary energy consumption does not exceed 120 kWh / sqm, the value of thermal bridges cannot exceed Ψ = 0.01 W / m (practically without thermal bridges), the value of the heat transfer coefficient (U) does not exceed 0.15 W / (mpK), the frequency of overheating (temperatures above 25 ° C) does not exceed 10% in summer.
The interest in energy efficiency in construction comes against the background of problems related to global warming: we consume a lot of energy for heating in winter and for cooling the windows in summer. All this energy is produced largely from the burning of fossil fuels and is lost due to poor insulation of buildings.


Is it worth building a passive house?
- Yes! It will drastically reduce your energy bills for heating and give you a higher degree of thermal comfort, keeping the temperature constant in the house. 

Is the system offered by Dia Doxa Folex approved?
-Yes, it is approved in Romania and supported by multiple patents obtained during over 20 years of research in the field of passive buildings. Laurențiu Breaz's work has been repeatedly rewarded in international exhibitions.

Is a house made of polyurethane elements healthy?
- Due to the fact that it prevents the development of bacteria and mould, a passive house made of PUR-ICF elements offers you a clean environment, which is preferable for people prone to allergies or respiratory problems. 

Is it a sustainable method?
- Polyurethane is obtained from oil, but is an ideal use of it. Instead of using oil for packaging that will be discarded in the environment, we propose to use this resource to build sustainable buildings that will drastically reduce the human impact on the environment without needing much energy for air conditioning.

Have other houses of this kind been built?
Yes, we have built passive houses and house extensions in Cluj County, in Paris, and several projects are underway. You can see more examples on the Projects page.

What are the benefits of a passive house compared to a conventional one?
- First of all, much lower bills than for ordinary house. Conventional construction constantly generates enormous costs with heating and cooling - in the context of rising gas and electricity prices, this is fundamental when choosing building materials. Instead of paying a lifetime for a minimum of comfort in your house, opt for a passive construction! Secondly, thermal comfort obtained easily, the temperature remaining constant.

Will such a passive house last over time?
- Passive houses made of polyurethane elements have the internal structure of reinforced concrete pillars that intersect to form a trellis structure. Once the concrete is poured into the channel network of the modular elements, the resistance structure of the building is formed.

Why choose polyurethane elements?
-Because low-density, closed-cell polyurethane has extremely high performance in terms of thermal insulation level. It is a versatile material that can be used in a wide range of constructive applications: energy accumulators, greenhouses or isothermal pools. The heat transfer on an outer wall of polyurethane elements is less than 5 W / m2 at an indoor-outdoor temperature difference of 40 ° C. PUR-ICF modular elements have a 50% lower thermal conductivity than polystyrene.

How strong is a house made of polyurethane elements?
-The building will have a monolithic structure due to the fact that the concrete in the floors and the load-bearing masonry of a level are poured at the same time. 


How does it behave in case of fire?
-Low density polyurethane foam does not maintain fire, and the walls can be covered with various tiles (eg magnesium oxide) that provide a higher degree of protection.

How do I go about building?  
-Dia Doxa Folex company only provides you with the materials and technical assistance for carrying out the construction works, but we will not actually carry out the work. You do not need specially qualified personnel to carry out our construction process.

Can I use these materials in areas with high seismic risk? Can it withstand the weather?
-Yes. The fact that the concrete fills the structure both vertically and obliquely ensures the structure an increased resistance. The house made of this material is a construction with a high coefficient of durability and resistance to external factors (water, vibration, wind action, earthquakes, etc.).

Does this system provide sound insulation?
- Yes, due to the physico-chemical properties of polyurethane foam.

What finishes can I do?
- The PUR-ICF elements are assembled with great precision, which results in a straight, flat wall that can be easily finished in any way.

Can it be adapted to any form of construction?
-Yes, it is a highly adaptable construction system that allows the construction of tall buildings of any shape. 

Do you design the building?
-We offer you some house projects drawn up by an architect, but if you want something else, we cannot offer you the design service.

How much does it cost?
In principle, a passive house made of polyurethane elements costs as much as a conventional one, but you will not have high expenses for air conditioning. For a precise offer, you must tell us the dimensions of the building.

We are at your disposal for more details!


Request a personalized offer!

In order to obtain a price quote, we need the precise dimensions of the building to be constructed. The size of the windows has an influence on the number of modular elements needed.


Headquarters: Str. Gării no. 288 A, Mirăslău, Alba, Romania

CUI / CIF: RO 38786046

Nr. Reg. Com .: J01 / 99/2018

+40 258 879 107

+40 787 519 595

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