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Thermal settlements

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During the last decade, the cost of building a house raised considerably, wether it is made of bricks, concrete or wood.
To this phenomenon, also ads the continuous raise of the energy costs for heating a house. For this reason, the vast majority of the population uses diverse technical solution for home insulation in order to improve the energy performance of the latter.
The houses that are very efficient in terms of energy have a bigger building cost that the classical ones, with 15 upto 20%. The payback period doesn't show immediatly - but in time through a reduction of heating costs. There is still a nasty phenomenon: the fall of purchasing power. This aspect drastically penalizes those who want to build a home. These are just as costs increase and income remain the same.
The problem is not simple! If we look at the overall costs, we can see that the fight against all forms of polution has become a primary goal, as well as significantly reducing our impact on the planet using healthier, cleaner, less energy consuming materials. By signing the Kyoto Protocol (December 1997) with subsequent ratification by 127 countries are committed during the period from 2008 to 2012 to reduce emissions by 5.2% against poluantes 1990. Taking into account the fact that the individual homes are the biggest enery consumers, the reduction must be made in that sector.
What do all these mean for a person who wants to build a new house?
Costs required for a better insulation.
To speak in numbers, today the average energy consumption for a dwelling is 240 KW/m2/an. The objective is to reduce consumption by 20% until 2012 and 40% until 2020. New tax policy, subsidies, and tax credits were developed to assist in this goal.


The new thermal regulations 2012 (RT 2012) replaced the RT 2005 standard has been mandatory since 2006 for new residential and non-residential houses.
For short, RT 2012 has two important objectives:
1 - reduction of primary energy consumption of 150 billion KW / h between 2013 and 2020.
2 - drastic reduction of CO ˛ emissions between 2013 and 2020.

Thus, there was established a limit of primary energy consumption limited to 50 kWh / m˛ / year (standard BBC (France), Minergie (Switzerland) or PassivHaus (Germany) = building with reduced energy consumption) for new construction applies to:
" Heating
" Production of hot water
" Airing
" Air conditioning
" Lighting system of the rooms
The limit of the average energy consumption, in accordance with the RT 2005 standard was 80 to 250 kWh / m˛ / year. The objective until 2020 is to improve the energy performance of new buildings by 50% compared to current performance.
RT 2012 thermal reglementation became mandatory for residential buildings from 01.01.2013.

The consequences of applying the thermal regulations

This will increase the number of homes with low energy consumption like bio-climatic or passive houses consistently reducing the need for heating and cooling.
In the same time, this will increase the cost side of RT 10 in 2005 to 15% for a house.

How to calculate the consumption?

Throughout the technical regulations, consumption is calculated as primary energy (Ep) and not as final energy (Ef).
The primary energy (Ep) is the first form of energy available directly from nature: wood, coal, natural gas, oil, wind, solar radiation, hydro, geothermal...
The final energy (Ef) is the energy delivered to the consumer for final consumption (gasoline at the pump energy at home ...).
Primary energy is often, not used directly, it is the object of transformation: the oil refining for gasoline or diesel, burning coal to produce electricity in a thermal power plant.
The primary energy consumption "EP" includes energy losses after the production and transport of energy to the place of final consumption.
In the case of electricity, it is necessary for a plant to produce 2580 W 1000 W to provide the consumer. Consequently 1 kW = 2.58 kilowatts Ep
The final energy is, therefore, often a multiple of primary energy (n), depending on the time of energy.

Résumé :

  • The final energy = the consumed energy (read on the counter)
  • The primary energy = the consumed energy + the necessary amount of energy to produce it.
  • The transformation energy : Ep = n x Ef

where " n " can have the following values deppending on the fuel used:
< Gas - n = 1
< Liquefied gas - n = 1
< Electricity - n = 2,58
< Wood - n = 0,6

Rules that must be fulfilled when building a low consumption house:

  • It should be as compact as possible: the more it will looks like a cube, the less it will have a surface of a wall or roof that will be a source of energy loss.
  • The living area must be bigger than the built area: all calculations are made in relation to m2. The lowest the number living square meters, the more unfavorable the calculations are.
  • The limitation of thermal bridge: thermal bridges are connecting areas in all buildings (floor-wall connection, connection window-wall, etc.). These bridges must be treated carefully to avoid energy loss.
  • The high sealing air leakage: leakage of air generates the greatest loss of energy - this can be avoided by putting a continuous vapor barrier film.
  • The passive solar warming: is the natural orientation relative to the south and windows optimization. Large openings shall be located as far as possible in the South, with double windows to let heat enter. Windows to the east and the north must have triple glazing, offering better protection.
  • Optimized ventilation: the goal is to bring fresh air into the house, to get non polluted air, minimizing the loss of hot air already present in the house, and not letting go the cold air more than necessary.
  • Reducing the cost of production of hot water: The hot water is the greatest sourse of energy from the heat ... the objective is to optimize it.
  • Automatized "antifreeze" security system: the system should allow keeping an internal temperature bigger than 14 °, even if there is nobody in the house. So, just a wood stove is not enough.
  • The summer comfort: summer comfort is measured by the highest temperature achieved during the hottest day of the year. The value depends on the region. The natural ventilation system, the absorption capacity of the natural heat through the walls and insulation can achieve the required performance.


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