Green Wheat

7693
Last modified by the author on 17/06/2019 - 15:50

New Construction

  • Building Type : Student residence
  • Construction Year : 2018
  • Delivery year : 2018
  • Address 1 - street : Lycée Xavier Bernard 86480 ROUILLé, France
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 695 m2
  • Construction/refurbishment cost : 1 120 000 €
  • Number of Dwelling : 13 Dwelling
  • Cost/m2 : 1611.51 €/m2

Certifications :

  • Primary energy need
    3.9 kWhep/m2.an
    (Calculation method : RT 2012 )
Energy consumption
Economical buildingBuilding
< 50A
A
51 à 90B
B
91 à 150C
C
151 à 230D
D
231 à 330E
E
331 à 450F
F
> 450G
G
Energy-intensive building

The wheat field offers a calm view, with constant light, conducive to concentration and rest. The project makes the most of this orientation by concentrating most student rooms. The proportion of the generic room has been designed to meet the desire for modularity of its layout. The window is conceived as a use, an additional space, in direct relation with the immense landscape proposed by the place. Around the main entrance are the daylight areas and the supervisor's room. The central circulation becomes a place of exchange and benefits from the natural lighting of the wind towers. There are lockers and forms of niches to sit and discuss in the chimneys and cool summer.

By its bioclimatic components, the project is exemplary in terms of sustainable development for the following reasons:

-It exploits the complex physical properties of lime-treated straw and mud brick in the margins of market standards,
- It uses, among other things, a climatic well, combined with a simple reverse flow ventilation (low tech) and recovers water to limit the use of drinking water in toilets.
- it exploits and controls the zenith light and air currents to manage the summer comfort
- it has been analyzed as part of the OBEC experiment and has been classified E4C2, yet deemed inaccessible (very high environmental performance), without having specifically sought it.
- it was conceived and carried out as soon as the sketch by a team of welded and prospective project management, committed to a permanent environmental approach.

  • Although it is a boarding school, we tried to spark the interest of high school students by offering workshops to discover construction techniques, in parallel with their educational program.

Sustainable development approach of the project owner

The Region has published its roadmap for sustainable development. The project "Green Wheat" served as a laboratory for the Region for the use of biosourced materials associated with the quest for energy performance and the reduction of greenhouse gas emissions. The result E4C2 is the proof that the squaring between E and C is not fantasy.

Architectural description

Agricultural high school embraces the scope of the trades of the land. Its architecture can also demonstrate the multiple ramifications of soil products.

The project uses plant materials, including local (straw and ground) and regional (hemp and wood) sectors.

During the study we oriented the constructive choices according to the development of the local sector. We also provided students with the results of this research.

Rainwater harvesting and composting are two other demonstrative assets of the relationship between architecture and agriculture.

The water recovered and stored in the three tanks is used not only for watering but also for maintenance and toilets.

The garden in the valley can then become a field of experimentation on a small scale to verify the combination of all these sources necessary for the growth.

The figure of the project is inspired by this organic cycle from the shape of the roof as a landscape draining water and light, to the material of the wall, clay plaster potentially from the same excavations of the site.

Thus all the axes of the project that our team has shaped over the course of many design exchanges have been conceived not only in the sense of the performance and the intrinsic quality of the building, but also in its ability to give a harmonious account of its behavior.

Nothing was left to chance: hygrothermal, acoustic and visual comforts, energy optimization, common space amenities, occupant health, durable structures and ease of maintenance.

Building users opinion

The energy bill of the school has not increased since the commissioning of the school.
Students are good in winter as in summer

If you had to do it again?

We would reproduce it exactly the same way.

See more details about this project

 http://www.dauphins-architecture.com/les-bles-en-herbe/

Photo credit

Dauphins architecture

Contractor

    Région Nouvelle Aquitaine, Antenne de Poitiers

    Cécile Varache cecile.varache[at]nouvelle-aquitaine.fr

Construction Manager

Stakeholders



    Other consultancy agency

    AMOES

    Julien Staal julien.staal[at]amoes.com

     https://www.amoes.com/

    OBEC engineer

Contracting method

Separate batches

Type of market

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Energy consumption

  • 3,90 kWhep/m2.an
  • 117,00 kWhep/m2.an
  • RT 2012

Envelope performance

Systems

    • Wood boiler
    • Canadian well
    • Other hot water system
    • Wood boiler
    • Canadian well
    • Nocturnal Over ventilation
    • Free-cooling
    • Canadian well
    • Solar photovoltaic
    • Wood boiler
    • Micro wind

Urban environment

  • 1 890,00 m2
  • 860,00 %
  • The wheat field offers a calm view, with constant light, conducive to concentration and rest. The project makes the most of this orientation by concentrating most student rooms. By taking advantage of the first rays of the day, students will see their use of artificial light decrease and will see the benefits of natural light.

Product

    Bale of straw

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    The straw boot has been appropriately accepted by the contracting authority, in particular because it is integrated in current construction technique, professional rules in support.


    climate well

    Elixair

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    The name "climatic well" refers to passive duplication in pre-treatment of fresh air (summer + winter)

    The Region knows the process. The user has observed that pretreatment makes the incoming air more comfortable.


    EP recovery tank

    Ecociter

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    two units:
    one dedicated to irrigation water
    the other in relay of the consumption of the toilets (WC only): objective 50% of EP

    The Region knows the system.


    O'Box

    EHTECH

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    Gray water heat recovery system

    The Region has tested this system. Looking back on experience
    User idem

Construction and exploitation costs

  • 1 120 000

GHG emissions

  • 11,00 KgCO2/m2/an
  • Experimentation E + C- / OBEC Program

  • 50,00 année(s)

Life Cycle Analysis

    The Wood Framing Wall is the lightest, least impacting structural mode (40% less than CLT, 90% less than concrete).

    Straw is the only material with a negative carbon impact and the biobased material has the highest carbon footprint.

Reasons for participating in the competition(s)

- Bio-based and recycled materials

Our choices were on the wooden frame, the insulating infill in straw bales, the thermal inertia contribution in mud bricks, the insulation of the cellulose wadding roof.

- Renewable energies

The building is powered by the wood boiler on the site of the agricultural college. The photovoltaic system, small capacity because the great intrinsic performance of the building requires very little compensation, and the small wind turbine inserted in the roof, produce electricity.

- Zero energy building

True to its DNA, the design team has addressed the issue of positive energy through a drastic process of reducing the need for energy before requiring the implementation of complex, expensive and polluting technological solutions.

This approach is completed in the second place by natural ventilation devices, geothermal (climatic well used in the summer to passively cool the building, winter to preheat the fresh air), heat recovery on greywater (in the showers). Electricity is produced by a wind turbine and photovoltaic panels. Rainwater is collected in two large underground tanks to feed flushing toilets in the toilets and water the green spaces.

- Health and comfort

The hygrothermal comfort conditions have been greatly improved compared to conventional constructions, by exploiting the properties of natural materials. The straw offers an excellent phase shift and thermal damping: indeed only about 5% of the solar heat wave passes through the straw bale, and arrives inside with a phase shift of 10 hours. In addition, the straw and the raw earth regulate the humidity in the interior air thanks to their properties (nature of the fibers and microstructure of the ground). Finally, neither of them diffuse pollutants into the indoor air.

- Low carbon

Bioclimatic architecture and natural matter (wood, straw, lime, raw earth) are at the heart of our approach to positive energy. The massive use of wood and straw, both storing carbon, strongly favors the reduction of the project footprint. The contribution of inertia by uncooked mineral matter (raw earth) logically complements our overall approach.

Building candidate in the category

Bas Carbone

Bas Carbone

Prix du public

Prix du public

Prix des Etudiants

Prix des Etudiants

Green Solutions Awards 2019 - Bâtiments France
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gauthier claramunt

architecte co-gérant


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Green Solutions Awards 2019 - Bâtiments France