In the construction of new homes, there are now several types of green homes. Before choosing a builder, here are the different ecological houses and their usefulness for the environment. Overview of the different green houses.
BBC House: the most widespread
Today, 17% of new homes built in France meet the BBC standard, Low Consumption Building. This BBC label aims to set a maximum limit for the energy consumption of new buildings for 5 primary uses: heating, ventilation, air conditioning, hot water and lighting. Depending on the altitude, the geographical area, the living space, the new BBC house will consume on average 50 kWh of primary energy per m² and per year.
From 1 January 2013, all building permits will have to meet this standard, this will be the new thermal regulation for all buildings, RT 2012.
Bioclimatic house: using the resources of the place
The bioclimatic house uses to its advantage the climate and the environment of the place of its implantation. The bioclimatic house could be like common sense.
Examples: orient the new house in the south to heat it for free, use deciduous trees to shade the summer, install the living rooms in the south, when the rooms to the north serve as energy buffer ...
Alternative to heating and air conditioning, the bioclimatic house tries to leave out heating systems considered too expensive like solar collectors and other heat pumps. On the other hand, it favors building and insulation materials that allow temperatures to stabilize, both by the accumulation of calories from the sun in winter and by maintaining freshness in summer.
The bioclimatic design is used in particular for the construction of a high environmental quality building (HQE).
Passive house or very low energy consumption
The principle of the passive house is that the heat released by the interior of the house (inhabitants and appliances) and that brought by the outside (sunshine) is enough to heat the house. Most passive houses are found in northern European countries, Germany and Switzerland.
If as for the bioclimatic house, insulation is the basic principle of the passive house, the credo of the passive house is to avoid thermal bridging, heat loss in a way. Another important point of a passive house, to be able to value the contribution of the sun, thanks in particular to the numerous glazed parts. Count between 40 and 60% of glazed surfaces in the south! An additional construction cost of 20% minimum is required in France to obtain a passive house.
Positive house: produce more energy than necessary
A positive house produces more energy than it consumes. The calculation of the energy consumption of a positive house is established over a long period, usually a year. These positive energy buildings, or Bepos, are in fact passive houses associated with energy production units, such as photovoltaic collectors on the roof, solar heating, a heat pump or even a wood boiler. These positive new homes require a large financial investment at the time of construction.
The positive new house could correspond to the future standards of the 2020 thermal regulation, the RT 2020.
Green house does not mean healthy house
One of the criticisms made to bioclimatic, passive or positive houses is that they are not healthy or green at the base. The high environmental quality of the building in the end can be neither ecological nor social in the choice of materials used, in the standards of health and safety at work of workers ...
In fact, to better isolate or avoid heat loss, these homes can use non-ecological materials. The healthy house uses natural materials, chosen for their supposed low impact on their inhabitants, on the environment during their transport ... A healthy house is not necessarily energy neutral as a passive house is not necessarily healthy or organic for its occupants or construction workers. We must then evaluate the gray energy: the energy impact of the products on the environment.
Green house does not mean either house that fits the landscape
Technicity and innovation do not always mix with tradition and respect of local aesthetic codes. Photovoltaic or other sensors can sometimes not fit the traditional French stations. That's why in respect of local architecture, sometimes you have to sacrifice some gadgets. This is the choice made for example by MGM French Properties, a developer offering property for sale in the French Alps. Its eco-friendly chalets, using modern construction techniques, have found the right balance between respect for modern energy consumption requirements and a certain idea of what mountain housing should be. An aesthetic integration irreproachable both to the surrounding environment and surrounding buildings then becomes a guarantee of authenticity.