Gustave André School Extension

Last modified by the author on 16/05/2019 - 12:19


  • Building Type : School, college, university
  • Construction Year : 2018
  • Delivery year : 2018
  • Address 1 - street : Rue des Ecoles 26120 CHABEUIL, France
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 802 m2
  • Construction/refurbishment cost : 1 800 000 €
  • Number of Pupil : 170 Pupil
  • Cost/m2 : 2244.39 €/m2

Certifications :

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


  • Wood frame walls
  • Biosourced insulation: compressed straw 40 cm in walls and roof (R = 7 m²K / W) -Metallery in metal Uw <1.6 W / m²K-Sunscreen type Roller shutter or sunshade outside direction (according to orientation)


  • Connection to existing gas boiler of the school group
  • Emissions by room-driven radiators by 2-way valve - Double Flow ventilation (82% heat recovery, by-pass for summer conditions) - Photovoltaic panels: 224 m²

Sustainable development approach of the project owner

The main objective is twofold:

  • aim for energy excellence, with the BEPOS Effinergie level, and make the building an exemplary case of compensation for energy consumption through local production
  • incorporate a maximum of local materials and biobased, through the facade and wood frame, with insulation by straw bales (choice of companies and local suppliers)

Architectural description

This building presents a mixed structure:

  • The superstructure of the building is of the post / concrete beam type, with slab and intermediate floors also provided in concrete, so as to provide the necessary thermal inertia for the building
  • All facades, as well as the roof are made of wood / straw construction.

Photo credit

Simon Barret


Construction Manager


Contracting method

General Contractor

Type of market


Energy consumption

  • -87,00 kWhep/
  • RT 2012

    50% related to heating 5% ECS 13% lighting 1% distribution auxiliary 21% Ventilation auxiliaries 7% others (current outlet, etc ...)

Real final energy consumption

    33,50 kWhef/

    2 018

Envelope performance

  • 0,42 W.m-2.K-1
  • Box wall wood / straw with straw boots 40 cm thick U = 0.177 W / m²K
    Roof timber frame + straw box U = 0.186 W / m²K
    Low floor on solid ground, continuous insulation U = 0.174 W / m²K
    Aluminum joinery Uw = 1.6 W / m²K

  • 0,44
  • I4

  • 0,72

More information

The perfromances described above are derived from the calculation RT2012 and the calculation of consumption outside the scope RT (ratio) The renewable energy contribution allows to speak of positive energy building with needs of -88.5 kWhef /


    • Low temperature gas boiler
    • Water radiator
    • Individual electric boiler
    • No cooling system
    • Double flow heat exchanger
    • Solar photovoltaic
  • 317,00 %
  • The low temperature boiler used is the existing one, feeding the other part of the school

    Brise Soleil Orientables

Smart Building

    Simple and efficient management of HVAC systems: V2V-driven radiators and thermostats in every classroom.

Urban environment

    Located near the center of Chabeuil, 5 minutes walk from the town hall, the school is bordered:

    - college Marc Seignebos, in the immediate vicinity to the east of a district pavilion (single houses mainly) all around


Construction and exploitation costs

  • 46 326,00
  • 330 905
  • 2 737 553
  • 1 025 169
  • All costs above include VAT

Indoor Air quality

    Double flow ventilation with filters and flow rates measured at reception to ensure good air quality


    Utilisation de la STD pour vérification des températures estivales - optimisation choix et orientation des vitrage

    Calcul de Facteur de Lumière du Jour via le logiciel Dialux

GHG emissions

  • 4,70 KgCO2/m2/an
  • Based on RT2012 consumption

Life Cycle Analysis

    Use of straw to insulate thermally and acoustically the walls facing the outside + wood frame

Reasons for participating in the competition(s)

Le bâtiment est en construction ossature bois, et l’intégralité des façades extérieures est isolé par des bottes de paille (provenant du département). Ce choix provient d’une volonté de construction en utilisant les ressources locales et duplicables, faiblement émettrices de gaz à effet de serre.

Building candidate in the category

Low Carbon

Low Carbon

Users' Choice

Users' Choice

Green Solutions Awards 2019 - Buildings

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Author of the page
Simon Barret

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Green Solutions Awards 2019 - Buildings