Les Canaux: eco-rehabilitation in a circular, innovative and humanist economy


  • Building Type : Office building < 28m
  • Construction Year : 1882
  • Delivery year : 2022
  • Address 1 - street : 6 quai de la Seine 75019 PARIS, France
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 797 m2
  • Construction/refurbishment cost : 1 383 000 €
  • Cost/m2 : 1735.26 €/m2

Certifications :

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

From the services of Les Canaux to the association Les Canaux

The building "des Canaux" was built in 1882 for the administration of Les Canaux services in the 19th arrondissement in Paris. In 2010, the administration left the premises. In 2016, the City of Paris decided to turn the building into the Maison des Économies Solidaires et Innovantes, a showcase for the circular economy, supported by the association Les Canaux.

Chaired by Yann Arthus Bertrand, the association advises, trains and supports economic actors committed to solidarity and the planet, in France and internationally. It offers concrete tools to all those who wish to develop their social and environmental impact in their work or business.

In 2017, the City of Paris made the building available to the association to develop its activity.

The building needed to be renovated and adapted, and the City of Paris decided to make it an exemplary work site, in terms of the environment, particularly the circular economy, and solidarity. In Paris, the building sector accounts for 80% of energy consumption and more than 20% of the carbon footprint and produces around 1.9 million tonnes of waste per year.


Phase 1 of the works - 2016-2017

Phase 1 of the works concerned the interior refurbishment of the first and second floors, now used as offices. 95% of the materials, products and equipment used were reused, bio-based and/or eco-labelled. 95% of the materials, outgoing products and waste from the site were reused or recycled. The City of Paris, which acted as project manager and project supervisor, won the Territoria de bronze award in the "Public Space Development - Urban Planning" category from the Observatoire National de l'Innovation Publique in 2018 for this work.


Phase 2 of the work - 2020-2022

In March 2020, the City of Paris signed a design-build contract to launch phase 2 of the renovation of the Maison des Canaux with the same objective, a building that is as virtuous as possible, particularly in terms of the circular, social and innovative economy. The consortium headed by the Grand Huit architectural firm was selected. The building site was handed over at the beginning of March 2022 after one year of work.

The programme of works for phase 2 consists of:

  • improving the building's energy performance (insulation, ventilation and innovative heating);
  • creating an outdoor terrace with a pergola, allowing the extension of the Canals' activities and integrating an access ramp for accessibility for all;
  • redesigning the ground floor and the basement to improve the reception of the public and the functionality of the building.

The design-and-build contract amounts to €1.7 million (including tax), for which the City has received 3 co-financing sources: the stimulus plan (€465,000), the Ile de France Region (€18,000) and the Parisian participatory budget (€100,000).

The project develops many innovations:

  • a pioneering building in reuse and unique in France, with the majority of the works made from second life materials exclusively from the Ile-de-France region. It is worth noting that more than 90% of the terrace is made of reused materials, including the metal structure of the shell;
  • the installation of natural ventilation with heat recovery, a very rare example in rehabilitation;
  • the rehabilitation of a traditional Parisian interior insulation technique, plaster on wood lath, thanks to a fire resistance test;
  • a major mobilisation of SSE structures in the Ile-de-France region: in the project management team, the craftsmen suppliers and the works companies.
  • A recovery rate of more than 90% for materials and waste.

An atypical and local grouping

Rare in projects of this scale, the design-build contract has enabled a unique collaboration in the service of responsible construction.

The Grand Huit architectural firm, leader of the winning consortium of the design-build contract, has placed the human element and the preservation of resources at the heart of its practice. It formed a group of project managers and craftsmen, mostly from the Social and Solidarity Economy, who worked hand in hand from the project's outline. The majority of the cost of the work was allocated to two integration companies in eastern Paris (Travail et Vie and Apij-Bat). The other companies in the contract, their subcontractors and suppliers, also located in an area close to the project, are key players in the field of reuse and solidarity in the Ile-de-France region.

The Grand Huit architectural firm was the perfect conductor of the operation, and succeeded in creating a poetic and sensitive architecture from its values.


Key partners in the success of the project

To carry out this operation, the City of Paris was assisted by Tribu Energie in improving energy performance and installing renewable energy heating, from the development of the programme to the acceptance of the work, and in assessing the building's greenhouse gas emissions (construction products and energy) and the carbon gains from reuse.

It is also supported by Ekopolis as part of the Bdf - Bâtiments durables franciliens (sustainable buildings in the Parisian region) approach, a support, evaluation and learning system for construction and rehabilitation operations. The project was awarded the Bdf Gold level, the highest recognition of the support system, in the design and implementation phases.

Bellastock, in the framework of the European project Facilitating the circulation of reclaimed building elements in Northwestern Europe (FCRBE), contributed its expertise on the insurance of the reuse of metal beams, donated by Est ensemble and Sequano. This feedback was presented to the European partners in Brussels by the City of Paris.

Inter-site synergies have been set up internally by the City of Paris and with many other contracting authorities to recover reused materials. In particular, the APHP, Est-Ensemble and its developer Sequano, Seine Saint Denis Habitat, the RIVP and Elogie-Siemp have contributed to the project through their donations. The physical and digital reuse platforms were also widely solicited.

The Centre Scientifique et Technique du Bâtiment (CSTB) conducted the fire test, which made it possible to experiment with a thermal screen composed of 100% bio-geosourced materials from the Ile-de-France region, wood lath and plaster coating, and thus to do away with the metal lattice, which has a heavy carbon impact, imposed by fire safety regulations.


Sharing experience

This demonstrator also has an educational purpose. Various site visits have been carried out. They have enabled about a hundred Parisians to visit the site and more than 50 employees of the Parisian community.

The City of Paris worked with the service provider Wild Time Records to capitalise and formalise the lessons learned from this operation in various communication media (article, video, motion design). These materials are available on the website: passerelle écologique paris, a platform dedicated to eco-responsible construction by the City of Paris.


Circular building paths

In order to perpetuate and develop circular economy practices and in particular reuse, the City of Paris (DLH), Les Canaux, Ekopolis and the Scop Grand Huit have experimented with a training scheme called "Les Chemins du Bâtiment circulaire" as part of this operation.

This is a theoretical and practical training course for the entire chain of actors, project owners, project managers and workers. The mix of participants, city employees and outsiders (landlords, architects, local mission, etc.), is sought to encourage the sharing of knowledge. For the first session, participants included City of Paris operations managers, social landlords, private architects, City of Paris masons and carpenters, and agents of integration companies.

Supported by the Ademe and the participatory budget, this scheme aims to be extended to other sites, including those of the City of Paris.


Mobilisation of the City of Paris employees

The City of Paris led the rehabilitation operation.

The project management team from the Housing and Habitat Department (DLH) received the City of Paris' internal innovation trophy in the ecological and climate challenges category in November 2021.

The DLH also worked in close collaboration with all the other departments. The operation once again revealed the abundance of professions and skills within the City of Paris.

Building users opinion

The occupants are very satisfied. Their needs have been taken into account and the philosophy of the work implemented highlights the association's missions.

See more details about this project


Photo credit

Grand Huit


    Ville de Paris - Direction du Logement et de l'Habitat

    christelle.davrieux[a]paris.fr ; isabelle.lardin[a]paris.fr

Construction Manager

    Grand Huit - Scop d'architecture



    Thermal consultancy agency



    BET heating ventilation water management

    Structures calculist



    BET structure

    Site manager

    Les Canaux


    Association for the promotion of solidarity and innovative economy

    Construction Manager



    BE reuse metal structure

    Assistance to the Contracting Authority

    TRIBU Energie


    AMO energy performance




    Technical control




    Safety and health protection coordination


    Travail et Vie


    Cleaning, logistics, site life and sorting management - Integration company


    Duarte Construction


    Structural work and demolition


    APIJ-BAT Coopérative

    Finishing work - Work integration company










    Général Métal Edition


    Structural steelwork (subcontractor)


    SARL David et fils


    Exterior carpentry (subcontractor)




    implementation of a load lift (subcontractor)




    Training in dry stone construction (subcontractor)


    A Travers Fil


    Realization and installation of a reused solid oak trellis for the fence of the outdoor terrace (subcontractor)


    Atelier Rare


    Manufacture and installation of end grain parquet (subcontractor)


    Les Résilientes

    eugenie.de.lariviere[a]gmail.com et geraldinetubery[a]orange.fr

    manufacture of tapestry from reused carpet and draperies and curtains in reused fabric




    Realization of macramé filling of the gates for the closure of the outdoor terrace (subcontractor)

Contracting method

General Contractor

Energy consumption

  • 96,10 kWhep/m2.an
  • 98,30 kWhep/m2.an
  • RT existant

    - 58.3% heating (wood boiler);
    - 39.2% lighting;
    - 0.6% ventilation;
    - 1.9 auxiliaries (DHW is not counted in the existing RT calculation for this type of building).

  • 208,10 kWhep/m2.an

Envelope performance

  • 0,94 W.m-2.K-1
  • The volumetry of the building has not been modified. Nevertheless, complete interior insulation has been installed on the exterior walls of the ground floor and R+1 (the exterior walls of R+2 and the attic already benefited from interior insulation). In addition, the majority of the single-glazed exterior joinery has been replaced by double-glazed joinery.


    • Wood boiler
    • Individual electric boiler
    • No domestic hot water system
    • No cooling system
    • Natural ventilation
    • Double flow heat exchanger
    • Wood boiler

Life Cycle Analysis

    The City of Paris commissioned Tribu Energie to carry out an LCA of the works carried out targeted on the construction product and energy indicators and an LCA without reuse, by replacing the materials and products of reuse with new equivalents.


    • Inondation/Crue lente
    • Sécheresse géotechnique (Retrait-Gonflement sols argileux)
    • Îlot de chaleur urbaine

    The attached climate risk assessment tool for the existing building before works highlighted three types of building sensitivity at different levels:

    • medium sensitivity to the heat wave hazard => In response, the project creates an island of freshness by installing vegetation on the outdoor terrace. It improves summer comfort with the installation of blinds on exposed windows and shade veils on the terrace. The terrace pergola and plantings have been designed to facilitate the growth of shade climbing plants. The operation of the natural ventilation is adjustable allowing ventilation at night to bring freshness and closing the day to keep the freshness. Joinery has been changed with better thermal resistance. The interior insulation of the walls also improves summer comfort.
    • high sensitivity to the hazard of drought and shrinkage swelling of clays -> In response, the recovery of part of the rainwater on site makes it possible to be economical in the use of drinking water and to compensate upstream for the drought risk
    • strong sensitivity to the flood hazard -> In response, the project tries to mitigate the risks upstream with, in particular, the recovery of rainwater on site for watering the plantations and the water supply to the toilets. In addition, low-tech was implemented as soon as possible to make the building functional even in the event of a power cut due to flooding: natural ventilation, manual handling of removable systems (partitions, gates, blinds, etc.)


    To find out more about adapting the building to climate change:

    Click here

Water management

    A rainwater harvesting system has been put in place to collect runoff water from the roof of the building. The capacity of the stormwater storage tank is 6 m3.
    This tank is connected to a rainwater management module which supplies the toilets on the ground floor, R+1 and the plant watering outlets on the outdoor terrace.

Indoor Air quality

    A double-flow natural ventilation system with heat recovery has been put in place to guarantee air renewal in the large room on the ground floor. The latter has a surface area of approximately 130 m² and serves as an exhibition room, meeting room or even a workshop during events open to the public.

    This ventilation system, made up of 4 modules of approximately 450 m3/h, is simple and incorporates little technology, hence its robustness and durability over time.

    It is energy efficient compared to a double-flow mechanical ventilation system:

    • in winter, it recovers approximately 50% of the heat extracted;
    • in summer, thanks to the inertia of the building, the association with the possibility of opening the windows, the large room reaches a level of hours of discomfort (resulting temperature higher than 28°C) of 14 hours per year for a continuous occupancy of 45 people.

    Finally, 3 CO2 probes positioned at opposite corners of the large room manage the opening of the ventilation registers by means of a "low tech" and innovative management system thus allowing the renewal of air.

Health & Comfort

    The double-flow natural ventilation system described in the "indoor air quality" tab provides comfort in winter thanks to the recovery of heat from the extracted air flow. Also, it allows a natural renewal of air which makes it possible to limit the concentrations of CO2.



    Génie climatique, électricité / Ventilation, rafraîchissement

Construction and exploitation costs

  • 171 330
  • 1 383 000
  • 583 000
  • The total cost is that of the design-build contract with the Grand Huit group for studies and works.

Urban environment

An industrial site until the 1970s, the Bassin de la Villette is now a cherished place to stroll for Parisians. The Maison des Canaux, a former building of the administrative department, bears witness to industrial activity. With increasing attendance, the Bassin de la Villette is a place of breathing and reconnection with water, birds, boats that opens up a perspective of Greater Paris via the Canal de l'Ourcq.

Located at the junction of the Quai de la Seine and Place Stalingrad, the building occupies an exceptional urban space. It opens an urban sequence towards the MK2 cinema, another preserved witness to the commercial past of the basin, a real major logistics center of the capital. Open to the city, surrounded by public space, the building is accessible by cyclists and walkers, by the main axes of gentle traffic laid out along the water.

The project strengthens the building's connection to the public space with the installation of a calade ramp which provides level access to a terrace and to the ground floor accessible to the public. This exterior layout has been designed to accommodate biodiversity. The low wall, the dry stone calade and the large trellis support perennial and native vegetation. Existing rose bushes have been carefully transplanted into the new layout. Nesting boxes for the existing sparrow colony have been added and the flora has been designed to accommodate this small bird, protected in Paris.

Rainwater is collected from the roof to water the plants. The terrace becomes a shady refuge in summer.

Parking spaces

9 m² of bicycle storage created in the basement.

Building Environmental Quality

  • Building flexibility
  • indoor air quality and health
  • biodiversity
  • works (including waste management)
  • consultation - cooperation
  • acoustics
  • comfort (visual, olfactive, thermal)
  • waste management (related to activity)
  • water management
  • energy efficiency
  • renewable energies
  • maintenance
  • building end of life management
  • integration in the land
  • building process
  • products and materials

Reuse : same function or different function

    • Structural works
    • Structural framework
    • Facades
    • Locksmithing-Metalwork
    • Indoor joineries
    • Outdoor joineries
    • Floorings
    • Partitions
    • Isulation
    • Suspended ceilings
    • Raised floors
    • Electricity
    • Plumbing
    • Landscaping
    • others...

    Terrace :

    • Metal beams (IPE, HEA, Tube, Purlin, Plates): 8.6 tons
    • Metal beams (L and Flat): 2.1 tons
    • Decking of the terrace: 80 m² (including 235 ml of joists)
    • Low wall, calade (disabled access ramp), planters: 57 m3 of stones
    • Rubble: 3 m3
    • Topsoil: 2 m3
    • Filling of portals: 5 km of climbing ropes
    • Wooden trellis: 55 m²
    • Shade sail: 90 m²
    • Bar grid: 1 unit
    • Bricks: 4 m²


    Work inside the building:

    • Removable partitions: 80 m²
    • Ground floor insulation: 76 m² of wooden laths + 35 m² of MDF wooden base
    • R+1 insulation: 200 m² of carpet covering + 270 m² of glass wool + 27 m² of MDF wooden base
    • Glass wool ventilation ducts: 75.8 m²
    • False ceilings Ground floor: 12 m²
    • Furniture: Cupboard: 6 m², worktop: 1 unit, benches: 2 units,
    • Doors: 10 units
    • Hardware associated with doors and furniture: at least 10 handles, locksmithing...
    • Sanitary: sinks: 1 unit, toilets: 2 units, basin/sink: 5 units
    • Polycarbonate: 5.12 m²
    • Windows: 3 units
    • Shade sails: 90 m²
    • Blackout curtains: 100 m²
    • Blackout slats: 15 m²
    • External blinds: 160 m²
    • Floors: 27 m² of parquet, 45 m² of restored parquet, 4 m² of standing wood mosaic
    • Baseboards: 70 ml
    • Floors: 33 m² of terrazzo steps + 18 m² restored, 4 m² of concrete slabs,
    • Wall tiles: 10.5 m²
    • Electricity: 2P+E sockets: 36 units, RJ 45 sockets: 18 units; switch: 1 unit;
    • Lights: LED strips: 11 units; light suspensions: 3 units; Spot light: 1 unit
    • BAES: 15 units
    • Electrical outlets: 66 units
    • Switch: 4 units
    • Electrical panel: 1 unit
    • Cable trays: 32 m
    • Faucets: 91 units
    • Cork: 300 liters
    • Radiator: 1 unit
    • Sound diffuser: 3 units
    • Light diffuser: 2 units
    • Fire alarm panel: 1 unit
    • False ceilings in parchment paper: 27 m²


    Structure of the terrace:

    • Steel beams (IPE, HEA, Tube, Panne) from a shed demolished by Sequano and donated by Sequano and Est Ensemble, transformed and adapted by GME
    • Metal beams (L and Plats), steel decommissioned by the steel mills and bought by GME

    Decking of the terrace:

    • Dismantling of Parisian landing doors in oak wood from the work of the social landlords RIVP (donation) and Elogie-Siemp (donation) and from the Réavie platform (purchase), transformation into cleats and installation by Atelier R-ARE
    • Dismantling of windows from a Parisian building site and transformation into moabi wood strips by Atelier R-ARE

    Low wall, calade (access ramp for disabled people):

    • Stones (limestone and millstone) and rubble from the demolition of the building walls and reused on site for the base of the terrace by Travail et Vie
    • Paving stones and kerbstones from the City of Paris platform and used for the low wall and the calade by Elips and Travail et Vie


    • Topsoil from the site's planters (removal, amendment and repositioning) by Travail et Vie


    • Filling of the gates: use of climbing ropes from sports shops and climbing centres recovered by Grand Huit and laid in macramé by Travail et Vie and Lauclem


    • Dismantling of Parisian landing doors made of oak wood from the work of the social landlords RIVP (donation) and Elogie-Siemp (donation) by Atelier Rare and transformation and adaptation into trellis by A Travers Fil

    Shade sails:

    • Creation of a flexible sail by Travail et Vie and Stu-Dio from PVC tarpaulins from the Réserve des Arts and installation by Travail et Vie

    Barrier grille:

    • Removal and re-installation at another location


    • Removal and relocation of facing bricks.


    Work inside the building: 

    Removable acoustic partitions:

    • Creation of removable acoustic partitions from textile scraps from a tailor and an insulator made of recycled cotton by Les Résilientes and installation by Les Résilientes and GME (holding and lifting device)

    DRC insulation:

    • Wooden laths from African content wood supplied by Esiam, chestnut laths from the Le Bon Coin platform and oak wood from the ApijBat workshop: recovery and adaptation by ApijBat
    • MDF wood base from a commercial event and installed by ApijBat 

    Insulation R+1:

    • Creation of a tapestry from carpets from trade shows by Les Résilientes and installation by ApijBat
    • Purchase from the Réavie platform of glass wool and installation by ApijBat
    • Recovery of MDF wood baseboards from an event and installation by ApijBat

    Insulation of the hoppers, a wall, the goods lift and the ventilation ducts: 

    • Purchase from the Réavie platform of glass wool and installation by ApijBat

    False ceilings on the ground floor:

    • Recovery of wooden radiator covers from the Les Canaux house, adaptation and installation of false ceilings by ApijBat


    • Synthetic material worktop bought on the Cycle up platform by Grand Huit and installed by ApijBat
    • Paillasses given by the APHP of a Parisian building site and recovered by Travail et Vie and installed by ApijBat as office tables

    Interior joinery:

    • Doors: adaptation of the existing doors to the places reorganized by ApijBat and recovery of a door of re-use of another building site

    Hardware associated with doors and furniture:

    • Recovery of handles and locks from the various doors and furniture to be reused

    Sanitary facilities:

    • Removal in conservation of 3 washbasins and 2 toilets by Travail et Vie and re-installation by ApijBat
    • Purchase by Grand Huit of a double washbasin on the Silensi platform
    • Purchase of a single sink unit by Grand Huit on the Cycle up platform 


    • Installation of a polycarbonate from an ApijBat workshop as overglazing on the ground floor
    • Removal of double glazed windows in the ground floor and re-installation of these windows in another location by ApijBat

    Solar protection: 

    • Creation of blackout curtains from cotton (grandmother's sheet) by Les Résilientes
    • Production by Travail et Vie and Studio of external blinds from plastic packaging sheeting from the Arts Reserve and installation by Travail et Vie


    • Recovery of parquet flooring from a City of Paris site and installation by ApijBat
    • Restoration of the existing parquet floor by ApijBat
    • Removal and restoration of granito steps from a Seine Saint Denis Habitat demolition site by Travail et Vie, installation by Duarte
    • Restoration of existing granito slabs
    • Creation of concrete slabs from the walls of a car park on a Parisian site by Bégo réemploi and installation of the slabs as a floor covering by ApijBat
    • Creation of standing wood and plaster mosaics from the remains of doors by Atelier Rare and installation of the mosaics on the floor by ApijBat and Atelier R-Rar
    • Creation of skirting boards for the ground floor and first floor from dismantled doors by Atelier R-ARE

    Wall tiles:

    • Careful removal of cement tiles from the ground floor of the ground floor by Travail et Vie and re-installation of wall tiles in the bathrooms by ApijBat
    • Production of terracotta tiles by Stu-Dio from planter soil and soil from the Grand Paris Express and installation by ApijBat as wall tiles in the bathrooms


    • Realisation of slats to ensure ventilation and hide the hoppers, from carpets recovered from event fairs by Les Résilientes.   

    Ventilation grids:

    • Recovery of radiator grids from the Les Canaux house by Travail et Vie and adaptation and installation by ApijBat


    • Recovery of sockets and a switch from Parisian building sites by and installation by SME
    • Removal and installation of electrical sockets, switches, electrical panels, cable trays and sound diffusers by SME
    • Removal and re-installation of BAES, a fire alarm system by SME 


    • Recovery of LED strips from a Parisian site and installation by SME
    • Removal and installation of LED strips and light diffusers by MHE
    • Purchase of hanging lights made from waste by Kataba and Cornichonstudio by Grand Huit 


    • Removal and installation of radiators and taps by Bosio


    • Recovery of cork scraps from the R+1 insulation by Travail et Vie and use in the light screed of the granito steps by Duarte
    • Removal and installation of the false ceilings in greaseproof paper of Fritz Jacquet Junior by ApijBat. 

    A donation transfer contract between the City of Paris and the donor was drawn up for the RIVP doors, the APHP benches and the granito steps of Seine Saint Denis Habitat. A partnership agreement was signed between the City of Paris, Est Ensemble and Sequano for the donation of metal beams, with an annexed contract for the transfer of said beams between Sequano and GME.

Sustainable design

    1. Reuse of metal beams

    The project management team (the architect Grand Huit, TISCO, Bellastock) defined its needs: description of the expected characteristics, graphic representation, hypotheses of deposit, points of vigilance...

    Then several channels were mobilised to find the metal beams adapted to the project: network of partners of the City of Paris, Bellastock AMOE and the metal carpenter GME. The sites were then selected by Bellastock and GME on the basis of a re-use diagnosis with the building owner. This work led to the selection of a shed located in Bondy that was to be deconstructed by Séquano and Est Ensemble as part of the Rives de l'Ourcq Zac in Bondy. The project management team and GME proposed the oversizing of the structure, generated by the use of these beams, which was validated by the inspection office. 

    Est Ensemble and Séquano agreed to ensure the careful dismantling of the metal beams and to give them to the City of Paris. In return, the City provided logistics, all the engineering for the reuse and the asurantial subject, produced information media (video, article) and documentation which it gave to Sequano and Est Ensemble for their use. A partnership agreement was drawn up in this respect between the City of Paris, Est Ensemble and Sequano. It included in annex the transfer contract between Sequano and GME which was established when the beams were handed over. 

    As part of the FCRBE project, an agreement was signed between the City and Bellastock to be a demonstration site. Bellastock provided all the technical and insurance engineering for the beams: development of a reliability protocol, monitoring of this protocol, working group with the actors and exchange with the AMO Insurance of the City of Paris. The protocol implemented was validated by the control office, which reassured the City of Paris and GME insurers, so that there was no additional premium.

    The carpenter then retained the parts of the metal beams that were in good condition, assembled them mechanically and installed them on site. 

    What is good: re-use of metal beams in the structure, subject to the ten-year guarantee, without any additional premium. The new collaboration that (re)emerged between the project management and the craftsmen to co-design the work.

    What could be improved: the traceability of information on materials which would improve the quality of EDP and Reuse diagnostics, the quality of EDP and Reuse diagnostics with information on the history (e.g. date of the PC...) and the dimensions of the framework elements (e.g. length, type...) to optimise the search for deposits and the visibility of deposits which are still difficult to find today.


    2. Reuse of wood (parquet, landing doors)

    Several types of wood reuse have been tested:

    • reuse of wood floor: the City of Paris was in the process of depositing a parquet floor on another site at the time of the rehabilitation work on the Les Canaux house. The schedule and characteristics were compatible with the project. The architect Grand Huit validated the proposal. ApijBat then adapted the parquet strips and installed them.

    • Reuse of landing doors from social landlords:

    The architect Grand Huit defined his needs in collaboration with Atelier R-ARE and A Travers Fil for the decking of the terrace and the trellis: description of the expected characteristics, graphic representation, hypotheses of deposit, points of vigilance ....

    A major search for second life oak wood was carried out using the networks of the City of Paris (in particular the social landlords) and those of Atelier R-ARE.

    When bringing landing doors up to standard, social landlords have a significant source of wood, but most of the time they are unaware of the type of wood and whether or not it is possible to significantly recover the material. Work was therefore carried out in consultation between the City of Paris, social landlords and those of the Atelier R-ARE association to identify the most relevant sources. 

    Once the latter had been found and validated by the architect, the logistical arrangements (packaging, transport, storage) were defined and the lessor adapted its contract accordingly. A free transfer contract was signed between the landlord and the City of Paris.

    The landing doors were then dismantled (*) by Atelier R-ARE, part of the components were adapted and assembled by A Travers Fil for the terrace trellis and the other part was transformed by Atelier R-ARE for the manufacture of the terrace decking and skirting. The off-cuts from the components were used to make the interior wood/plaster mosaics. 

    What is good: giving a second life to a large and easily accessible pool of landing doors

    • What could be improved: the re-use diagnosis does not mention the type of wood used in doors or windows. We have experienced many failures in the search for sources. 

    What is difficult: (*) The careful dismantling of doors that have been armoured afterwards is painstaking and time-consuming for a qualified operator, so that the material can be reused.  


    3. Reuse of stones, paving stones, kerbstones using the "dry stone" technique

    The architect Grand Huit wished to use the "dry stone" technique to build the low wall and the access ramp for people with reduced mobility (PRM), or calade.

    To do this, it relied on the expertise of the Ecole Locale et Itinérante de la Pierre Sèche (Elips). Elips designed the low wall and the calade, trained Travail et Vie as well as students and city employees in the technique within the framework of participatory workcamps and supervised the work.

    The filling of the base of the terrace was made with limestone rubble and millstone from the careful deconstruction of the demolition walls by Duarte. Travail et Vie took care of the sorting and logistics of these stones as well as their installation. 

    The low wall and the calade were mainly made up of paving stones and kerbstones from the Parisian road system. The City of Paris has a platform where they are stored, refurbished and adapted according to the needs of the technical services. The architect Grand Huit and Elips chose the ones that met the requirements of the work in terms of function and aesthetics. Travail et Vie took care of the logistics. 

    What is good: giving a second life to an important and easily accessible deposit, avoiding the use of cement and concrete

    What could be improved: start with a simpler work to realize like low walls in landscaped areas and only then continue with more complex works like the one realized in order to optimize the process. 

    The specifications of the works planned to favor the following order for the supply:

    1. Materials produced, biosourced equipment, resulting from reuse or containing at least 10% recycled material;
    2. Recyclable materials, products, equipment;
    3. Materials produced, equipment taking into account the overall assessment of the life cycle: eco-label, existence of verified environmental declaration sheets (FDES, PEP).

    In the event of recourse to other materials, the group had to justify that it had carried out research and found nothing.

    The biobased materials were also recyclable.

    Materials containing at least 10% recycled material:

    • steel beams for structural recovery of the building;
    • recycled cotton insulation for the ground floor room and removable partitions;
    • Fermacell for fire protection (boiler room, ventilation ducts, portico, fire door) and for insulation (dining room, sanitary facilities and false ceiling).

    1. Reversibility

    The specifications provided for reversible equipment and to favor mechanical, dry assemblies and to avoid glues if possible...

    Indeed, in order to limit the consumption of these materials, products, furniture and equipment, these had to be as far as possible:

    • removable;
    • adaptable;
    • robust and durable.

    The design had to be particularly sensitive:

    • structural choices;
    • the accessibility of the various construction elements (particularly for those with a short lifespan);
    • the assembly methods of the various products;
    • the choice of single materials;
    • the independence of building elements that have different life cycles ( layer theory );
    • the multiplication of commercial references for the same function;
    • ...

    The group responded: the terrace can be completely dismantled, without binder: the calade, the low wall and the planters were made using the "dry stone" technique, i.e. without binder, the trellis, the structure of the terrace and the decking are mechanically assembled like a "mechanic".


    2. Adaptability

    The adaptability of the room on the ground floor to meet the different uses of the association was an integral part of the specifications. The partitioning had to allow the following configurations: standing conference mode called "cocktail", seated conference mode called "plenary", mode called "board of directors", mode called "meeting" and mode alone in a group or small group and pop up mode store with large rectangular tables to allow exhibitors to display their merchandise.

    Grand Huit has set up with the help of GME and Les Résilientes an innovative system of ergonomic, simple partitions that do not clutter up the space once retracted.

    They were inspired by the system of sectional doors and the so-called “German” theater stage curtain. Once up, the textile partition covers the ceiling which it adorns and frees the room completely. No need for moving or storage without preventing the installation of light fixtures and other ceiling equipment. A flame retardant treatment by pre-soaking ensures the fire resistance of textiles without VOCs or formaldehydes.

    The work of Junior Fritz Jacquet which covers the cloud ceiling is not affected by these devices in this way.

    The specifications for the works stipulated that the following order of procurement was to be preferred: 

    • Materials, products and equipment that are biobased, derived from reuse or contain at least 10% recycled material;
    • Materials, products and equipment that are recyclable;
    • Materials, products and equipment that are recyclable; Materials, products and equipment that are produced taking into account the overall life cycle assessment: eco-label, existence of verified environmental declaration sheets (ESDS, PEP).  

    In the event of recourse to other materials, the grouping had to justify that it had carried out research and found nothing.

    It also asked for particular attention to be paid to the technical and environmental performance related to the quality and implementation of the products and equipment used, their maintenance and upkeep and use.

    • The service life of a construction product or equipment or the reference service life (see INIES database http://www.base-inies.fr/iniesV4/dist/consultation.html) makes it possible to identify the construction products with the longest service life.
    • An analysis must be carried out on a case-by-case basis, as well as the advantage/disadvantage balance between extending the service life (repair, maintenance, servicing) and replacing all or part of the asset.
    • In terms of automation, home automation or connected objects, the use of "low tech" or "low technology" solutions can, for example, be considered. They are characterised by the implementation of simple, inexpensive technologies, accessible to all and easily repairable, using common and locally available means without compromising the level of service provided.

    The consortium responded to these various points as follows: 

    1. Biobased materials

    Preference was given to bio-based materials, whether they were new or reused. 

    In addition to the reused materials mentioned above, you will find below the new bio-sourced materials: 

    • wood: framework for the insulation of the ground floor and first floor, furniture, windows, doors, window sills;
    • cork: insulation of the window embrasure on the ground floor;
    • straw: insulation of the ground floor window opening. A straw-gypsum insulation, which was tested for fire resistance during a previous project, was used.

    The paints used are class A+, eco-labelled, and low VOC emitting paints: Aquaryl Mat +, Aquaryl Velours + and a plant and mineral based paint from Natura Tassili (washable ecological paint, velvet tinted interior - exterior).

    2. Innovative materials

    The innovations concerned : 

    • the rehabilitation of a thermal screen composed of wooden lath and plaster for the insulation of the ground floor. A fire resistance test was carried out by the CSTB, with the technical support of researcher Arthur Hellouin de Menibus. You can find more information on the website: Insulation of the ground floor room - Passerelle Ecologique (passerelle-ecologique.paris) ;
    • the construction of removable partitions by craftsmen - see above;
    • the realisation of an insulation on the ground floor consisting of an insulator, a vapour barrier, a wooden framework and a wallpaper made of reused carpets. 

    3. Local materials

    The vast majority of the reused materials come from Parisian construction sites and the inner suburbs, mainly the 93 department.

    4. Low tech materials

    The low-tech equipment is essentially : 

    • the natural ventilation system which works by mixing hot and cold air;
    • the lifting systems of the removable partitions, the gates, the mechanism of the blinds: they are made up of pulleys and cranks and work with the force of the arms.

Environmental assessment

    Les résultats du calcul d'impact sont les suivants :

    Catégories CO2 évité (kg)  Consommation Eau évité (m3) Déchets évités (kg)
    Aménagements extérieurs 100 0,8512 226,373572
    Aménagements extérieurs / Serrurerie - Métallerie 0 0 0
    Charpente 26144,43975 137,5443603 583,3691144
    Cloisons 0 0 0
    Couverture 0 0 0
    Couverture / Aménagements extérieurs 0 0 0
    Eclairages 825,3294439 6,572118021 1116,157544
    Eclairages sécurité 101,5544921 6,720953741 180,4228528
    Equipements de génie climatique 0 0 0
    Equipements électriques 317,0916204 39,33104794 139,9612671
    Façades 110,956 0,602658 42,7984196
    Faux plafonds 0 0 0
    Faux planchers 0 0 0
    Faux-plafonds 0 0 0
    Gros-œuvre 122483,8354 826,5138738 159578,0445
    Installations sanitaires 538,690943 6,087830568 409,1163135
    Isolation 859,3645204 11,50477475 1161,759726
    Menuiserie ext 18247,7924 181,1200662 8522,143167
    Menuiseries intérieures 1364,797921 984,4354333 1804,880752
    Mobilier 362,2680317 2,482330673 279,2440916
    Peinture 0 0 0
    Plomberie 2270,45 30,88085 6065,646369
    Revêtements de sols 2008,295321 69,1387102 1340,53722
    Revêtements de sols ou muraux 200,145 0,4378 2535,679586
    Revêtements muraux 0 0 0
    Sécurité du bâtiment 0 0 0
    Serrurerie - métallerie 556,0813636 3,45763418 703,7955718
    VRD 0 0 0
      CO2 évité (kg)  Consommation Eau évité (m3) Déchets évités (kg)
    TOTAL 176491,0922 2307,681642 184689,93
      Km en petite voiture Nb de Baignoires rectangulaires nb d'années de déchets ménagers d'un français

Reproductibility and Innovation

    The project management team included an expert in circular economy from the City of Paris who participated in the elaboration of the works contract, the control office and the AMOA for the realization of the LCA, the drafting of the functional programme and the follow-up of the design and execution phases of the works. It also participated in the assessment of the operation, the formalisation of the feedback and its analysis.

    The City of Paris also benefited from the Bellastock coordinator of the European FCRBE programme for the technical and insurance aspects of the re-use of metal beams for the structure of the terrace.

    The rehabilitation of the Maison les Canaux (phase 2) was carried out under a design-build contract. A guide explaining the principles of the circular economy applied to the operation (including the conservation of the existing, the supply of re-used or reclaimed materials and the management of outgoing flows with priority given to re-use and re-cycling) was one of the parts of the works programme and each part of the works to be carried out made reference to it. Candidates were judged : 

    • Application phase:

    criterion 1 - 60%: skills in terms of integration, circular economy and eco-design

    criterion 2 - 40%: technical capabilities of the team in architectural and technical design, rehabilitation work, all trades and the circular economy;

    • Tender phase :

    criterion 1 - 45%: a sustainable and eco-responsible project for a resilient building, divided 50/50 between the consideration of societal, social and environmental issues and the quality of the circular approach

    criterion 2 - 35%: the functional, technical and architectural quality of the project (35%)

    criterion 3 - 20%: the price The maximum budget for the project was fixed and known to the candidates.

    The control office contract provided for basic and specific missions for non-routine techniques and time for the analysis of the group's proposals. The candidates were judged on their competence and experience in non-routine techniques and reuse.

    The selected grouping, whose leader is Grand Huit, chose to give priority to materials from re-use and was surrounded by actors involved in re-use and eco-construction. 

    Transport and logistics were handled by Travail et Vie, which was also in charge of cleaning and waste management for the group. In addition to the storage on site and in the group's premises, the City of Paris provided the group with a closed storage area near the site. 

    The obstacles and solutions identified were:

    • the search for reuse sources: the drafting of needs expression sheets by the project management team on reuse materials in the sketch phase made it possible to carry out the search from the beginning of the design and, if necessary, to adapt it. The City of Paris, the Bellastock AMOE and the associations and craftsmen of the group activated their various channels to find them. The City of Paris allowed the project management team flexibility at the different phases of the design to take into account the reused materials found;
    • the verification of the suitability for use: the mobilisation of companies and craftsmen, already competent in reuse, and of the reuse project management team, from the validation phase of the reuse materials, enabled the project team to benefit from their know-how and expertise to qualify the deposits. The choice of a control office that was already open to these issues then facilitated validation.
    • storage and logistics: the design-build contract made it possible to integrate this from the start. 
    • insurance: the work did not incur any additional premiums or difficulties thanks to the use of project management teams, companies and craftsmen already experienced in reuse, the support of the FCRBE coordinator, and an inspection office open to these subjects and already experienced in non-routine techniques and reuse.
    • the timetable: the acceptance by the contracting authority and the association Les Canaux, occupier of the premises, to extend the duration of the works when the reuse deposits were not available at the required time and the project management team to adapt the organisation of the works to minimise the impact on the timetable.
    • communication: a specific communication contract with Wild Times record was signed to produce videos and articles on the project and to update the Passerelle Ecologique - Construire Autrement à Paris : Cap ou Pas Cap ? website (passerelle-ecologique.paris), which presents the entire project and its feedback; visits were organised throughout the worksite and now, including a meeting and two visits to local residents to explain the project to them, participative workcamps for the construction of the low wall and the "dry stone" calade were organised by the members of the consortium 
    • training: a training programme called "Les Chemins du Bâtiment Circulaire" (Circular Building Paths) aimed at project owners, project managers and craftsmen was tested in order to raise awareness of reuse throughout the chain of actors and to demonstrate by example, on the building site, what can be achieved. 

    The work, in particular the demolition of the load-bearing walls, the cleaning of the floors and the opening, were part of the design-build contract.

    The coordination of the removal and cleaning work companies with those of the refitting was managed by the architect who integrated it into the overall schedule of the operation.

    This work was also carried out by the architect during inter-site synergies where coordination was necessary between the work of the two different clients.
    Example : demolition work on the Bondy hangar and construction work on the metal frame of the terrace.

    The storage of materials took place on the construction site, in the storage areas of the consortium and in the premises, La Commanderie, made available by the City of Paris for the consortium.

    The materials not reused on site, but still in good condition or capable of being restored, were given to the services of the City of Paris then to the actors of the Social and Solidarity Economy of the territory who so wished after having carried out research and publicity. to all those listed. A free transfer contract was then signed between the City of Paris and each actor.

    The other materials were systematically searched for a reuse channel, then recycling and then energy recovery by the City of Paris and Travail et Vie.

    • Example 1 - Plaster from joists: the City of Paris asked its laboratory to find out about the outlets in Ile de France for liming and plaster manufacturers for recycling. These two solutions having been ruled out, Travail et Vie had no choice but to send it to a landfill.
    • Example 2 - Glued PVC floors: the City of Paris mobilized Kaléi to recycle the floors into construction cones. Following its agreement, the City coordinated the evacuation of these soils between the services of the City, Work and Life, Kalei and its driver.

    In the end, the material recovery rate, excluding hazardous waste, is more than 97% and that of non-hazardous non-inert waste, more than 77%.

Social economy

    Candidate groups were judged on competence in the use of social integration up to 12% at the application level.

    The consortium selected, whose representative is the Scop Grand Huit, was made up of a large majority of actors from the Social and Solidarity Economy and Professional Integration.

    Project management team : only the BET structure is not from the ESS.

    • Scop d'architecture Grand Huit;
    • SWiTCH: collective of engineers for the heating, ventilation, plumbing BET;
    • Bellastock: cooperative society of collective interest (SCIC) of architects, AMOE reuse.

    Works team : Their lots represent more than 50% of the amount of the work.

    • Work and Life: “Help through work” association. It was responsible for the "Worksite life - Logistics - Sorting - Cleaning" lots, "Dry stone masonry and revegetation", "Wood work - Signage", "Textile works - locksmithing" and "Painting".
    • Apij-Bat Cooperative: SA cooperative with a board of directors (judicial liquidation on 5/04/2022). It provided the "Plasterwork, insulation, floor and wall covering", "Exterior joinery" and "Covering" lots.

    Subcontractors :

    • Itinerant Local School of Dry Stone: training association in the technique of dry stone;
    • Les Résilientes: association which is part of the Emmaüs Alternatives network and which produced the tapestries and slats in front of the hoppers from reused carpets, the blackout curtains and the hangings of the removable partitions from reused textiles;
    • A Travers Fil: association of carpenters who made the trellis for the terrace from the components of the doors;
    • Atelier R-ARE: member association of Construire Solidaire which ensured the dismantling of the doors, the construction of the decking of the terrace, the plinths and the mosaic in wood/plaster;
    • Réavie: association that manages physical reuse platforms.

Reasons for participating in the competition(s)

The Building sector in Paris accounts for 80% of energy consumption and more than 20% of the carbon footprint and produces around 1.9 million tonnes of waste per year, of which around a third goes to landfill, mainly materials and 2nd work products.

Concerned about these alarming figures, the City of Paris has set itself ambitious objectives in its Climate 2050 plan to make our buildings more virtuous, which it has translated into 10 concrete commitments in the Construction Pact published in 2021: rather to restructure than demolishing, reusing rather than throwing away, using biosourced materials, aiming for zero landfill waste, energy sobriety, low carbon…

For this, the City of Paris must be a driving force in its territory to develop and support these good practices, often carried by Social and Solidarity Economy structures and to encourage the structuring of circular construction sectors with the establishment of reuse platforms, but also to offer places of discovery and training.

These are the objectives of this rehabilitation, to make an exemplary project in this area, proving that it is possible to renovate an old building with materials from re-use, and to make it a high quality, functional and comfortable equipment.

This project must also raise awareness among project owners and Parisians about the benefits of the circular economy in construction. It is for this reason that a significant component is given to communication with the website, and the organization of visits and training, with participatory sites and meeting times with the teams offered throughout the project; and to experimentation with an awareness-raising system aimed at the entire chain of players, Les Chemins du Bâtiment Circulaire.

Building candidate in the category

Bâtiments tertiaires / prix de la rénovation

Bâtiments tertiaires / prix de la rénovation

Trophées Bâtiments Circulaires 2022

 2022 Circular Buildings Trophies
 materials and solutions
 circular economy
 tertiary building

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    Trophées Bâtiments Circulaires 2022