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Building an ecological house: what is a thermal study

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An ecological house is designed to consume very little energy on a daily basis. Its performance is validated by thethermal study who analyzes the design of the new house to predict consumption. I'thermal study, which makes it possible to produce the certificate of consideration of the RE2020 during the building permit, is a chance to verify that your future new house will be economical, and will guarantee your comfort for many years.

Ecological house: is the thermal study compulsory?

La RE2020, is the environmental regulation, which governs the new construction of buildings. Before, we were talking about thermal regulations. These regulations, like all those governing the construction of new houses, impose requirements so that the houses built are comfortable and of high quality. During the permission, it is therefore necessary to provide a certificate of completion of the energy feasibility study and consideration of RE2020 upon filing of the building permit. Upon completion of the work, it will also be necessary to provide the certificate of consideration of RE2020. The thermal study is the best way to achieve these two certificates.

To find out more, read our article New house RE 2020 in the South-West: what consequences for my project?

A thermal study to avoid exceeding the RE2020 thresholds

For construction to be authorized, it must not exceed certain thresholds defined by RE2020.

Low power consumption

The house should therefore not consume too much energy for heating, cooling and domestic hot water production.

Low greenhouse gas emissions

The thermal engineer analyzes the greenhouse gas emissions of the heaters and hot water production. In fact, this indicator prohibits, from 2022, heating exclusively with gas or with other fossil fuels.

To go further, we also analyze the greenhouse gas emissions throughout the home's life cycle. This means that greenhouse gas emissions are taken into account from the manufacture of materials, then during construction, and life in the building (heating, hot water), until demolition. and the building's end of life (recycling of materials, etc.). This measure thus favors renewable materials and wooden house.

Guarantee summer comfort

The law defines a number of degree-hours of discomfort in summer not to be exceeded. The threshold of 1250 DH corresponds to a period of 25 days during which the accommodation would be at 30°C during the day and 28°C at night.

An ecological house plays with the sun to guarantee the comfort of the inhabitants.

What is a thermal study?

A thermal study, is the result of expert calculations which determine, depending on the materials used, theorientation of the building, theinsulation thickness and equipment, what would be the annual energy consumption of the building. It thus makes it possible to check that the house respects the thresholds of the RE2020. Today, in fact, new houses must be low energy houses ou with the BBC. The energy consumption of these ecological houses, for heating, cooling, hot water production, ventilation and lighting should be as low as possible. The thermal study therefore analyzes all the parameters that contribute to the energy consumption of your future home.

Today, the thermal study is supplemented by the analysis of the life cycle of the building which calculates all the greenhouse gas emissions of the materials and the house.

The ecological house: a well-oriented house

Capturing the slightest ray of the sun to take advantage of free heat contributions, this is what a well oriented house. The control of solar gains makes it possible to recover the heat of the sun in winter, thanks in particular to well placed glazing. In summer, on the contrary, the house knows how to protect itself from the rays to avoid overheating. THE thermician therefore studies the environment of the house, the orientation of the glazing, but also the occultations such as the roller shutters, pergolas, vegetation…. The good orientation of the house also makes it possible to limit the use of artificial lighting.

Learn more: Which shutters in a new house?

home insulation

Create a thermal barrier between the inside and the outside of the house, is the role of theisolation. It is placed on floors, walls, roofs or attics. Its performance will depend on the nature of the materials used for the construction of the house, but also on theinsulation thickness. The performance of doors and windows is also taken into account. The thermal study also ensures the absence of thermal bridges.

Ventilation: key point of the ecological house

The renewal of the air in a house must be controlled to guarantee energy savings. It goes through a good airtightness of the House. Then a controlled mechanical ventilation ensures the renewal of the air and adjusts it to the real needs of the house and its inhabitants.

Production of heat and hot water

The thermal study then controls the equipment of the house. Pompe à chaleur, boiler, water heater… The performances of the planned heating equipment are analyzed and studied according to the geographical location of the house to anticipate their annual consumption. There electricity production by photovoltaic panels is also looked at.

To go further, read our article: Build a house without heating, or almost

The thermal engineer studies all the elements that make up the house to help design the most ecological house possible.

Who carries out the thermal study

THEthermal study is generally carried out by engineers independent thermal engineers or working for a thermal design office (BET). THE BET has ten-year insurance. The energy performance linked to the solutions they recommend is therefore covered by the ten-year guarantee.

What is the role of the thermal study?

Beyond the legal obligation, the thermal study is very interesting, because thethermal engineer has the know-how to help you make the best choices for your project. Increasingly complex, the RE2020 environmental regulations require significant skills and a real knowledge of software and calculations. The experience of the thermal engineer allows him to propose solutions to create high-performance buildings that meet the regulations, even in the most complex cases. If the future house does not have a well oriented plot, he will know which lever to insist on to achieve the performance required by this ecological house while retaining the architectural desires.

For more information read our article: New house in the South West: what is comfortable heating?

Thermal study at the completion of the works

On completion of the work, the client must hand over to the town hall theCertificate of consideration of RE2020. The latter is established, after an on-site visit, by an architect, or a technical inspector or a person competent to carry out an ECD or a contracted certifying body. It will often be based on the thermal study provided and the control of its recommendations on site. This document demonstrates compliance with the thresholds required by the regulations.




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