GENERAL INFORMATION RENOVATION PROCESS RETROFIT SOLUTIONS EVALUATION

Halle Bouchayer Viallet

ZAC BOUCHAYER VIALLET - 5 esplanade Andry Farcy

38000

Grenoble, France

Architect

Tandem Agence

3 rue Rotrou, 28 100, Dreux

contact@tandemarchitectes.com

02 37 43 80 15

Owner

SCI la COOP Enercoop Rhones-Alpes

frederic.marillier@enercoop-rhone-alpes.fr

User

Contact Details

Charlotte Beneteau

Sites et cités remarquables de france

c.beneteau@sites-cites.fr

Other Information

Most of the information comes from the architectural firm that worked on the project.

Visits
Frédéric Marillier - ENERCOOP Rhones-Alpes

This renovation project concerns the old HALLE REBATTET, located in an industrial zone in the heart of Grenoble. The latter is the winner of the call for projects "DEFFIBAT demonstrator buildings with low energy consumption", in Rhône-Alpes, in 2017. This building is the result of the complete renovation of the west wing of the Rebattet Hall (named after its previous owner), the east wing having been demolished to make way for a residential building. The object of the project concerns the development of the hall for use as offices and a restaurant. The mixed economy company Innovia, which is in charge of the renovation of the ZAC (concerted development zone) Bouchayer Viallet, undertook development work on the remaining wing with a view to its sale: closing wall of the hall to the east , roof, doors and windows.

GENERAL INFORMATION RENOVATION PROCESS RETROFIT SOLUTIONS EVALUATION

Energy performance

88,6 kWh/m2.y

Climate Zone H1c

Altitude 384 m a.s.l.

HDD 2897

CDD 128

Protection level Not listed

Conservation Area:
No

Level of Protection:

Building age 1900-1944

Year of last renovation:
2016

Year of previous renovation:
2011

Building use Offices

Secondary use:
Hotel/Restaurant

Building occupancy:
Permanently occupied

Number of occupants/users:
184

Building area Net floor area [m²]: 1100,0

Building typology:
Old industrial hall

Number of floors:
3

Basement yes/no:
Yes

Number of heated floors:
1

Gross floor area [m²]:
0,0

NFA calculation method:
SHON (fr)

Construction type

Masonry and metal structure for the frame

External finish:
Exposed stone

Internal finish:

Roof type:
Pitched roof

+ MORE - LESS

RENOVATION PROCESS

Architecture

BUILDING DESCRIPTION

The Halle Rebattet is a building belonging to the industrial heritage of the ZAC Bouchayer Viallet which was specialized in the production of cast iron networks. The building is simple, rectangular in exposed stone with a two-sided metal roof. It now accommodates offices with a co-working part as well as meeting rooms spread over the floors. A restaurant is located on the ground floor and overlooks the forecourt. The envelope is unchanged, without addition or extension. The openings are adjusted or created to take up the composition and bring light to the interior spaces. A large bay window replaces the existing large metal door, making the interior of the restaurant legible. The added elements respect the framework of the composition of the existing, in the industrial and graphic spirit. The stake of the project was to develop tertiary spaces in the existing industrial volume, in a constrained site with the strong presence of adjoining and city center context.

Urban context

Located at the western entrance to Grenoble, near the train station, the A480, and the city center, the district's strategic location is an asset for economic players. Companies like Elegia, Delta Drone, Bonitasoft or Groupe 6, one of the leading architectural firms in France, have set up there, as well as two company hotels. To support its attractiveness, 20,000 m2 of additional offices, including the installation of the Caisse d'Epargne headquarters, and a co-working space, will soon be added to the existing service offer.

State of repair

Conditions of the envelope

Before the renovation the building consisted of a large empty volume in good condition: with original masonry walls, an original metal frame and a roof that had been replaced. However, part of the soil was polluted, decontamination work was necessary.

HERITAGE SIGNIFICANCE

ELEMENTS WORTHY OF PRESERVATION

Several architectural elements of Les Halles represent the typical model of industrial buildings: facades, openings and exposed stones.

Heritage Value Assesment

The small hall is one of two industrial buildings preserved on the industrial wasteland of the Bouchayet Viallet site in Grenoble, which is now the subject of a vast development program. The building dates back to the turn of the century and was one of three penstock manufacturing and assembly plants for the hydroelectric industry on the site. The architecture is industrial and aims to be traditional and functional, combining masonry and a metal structure for the frame.

Aim of retrofit

Renovation

The challenge of the project was to develop tertiary spaces in an existing industrial volume, in a site constrained by a strong presence of adjoining buildings and context of the city center. The renovation works focused on the building envelope and the equipment.

Was there any change of use?

This former factory has become a tertiary place, hosting a co-working space and a restaurant.

Lessons learned

The main lesson learned during this work is the need to take into account the share of structural impact in the budget, due to the location of the building in a seismic zone.

Stakeholders Involvement

Public sector
Région Auvergne-Rhône-Alpes
1 esplanade François Mitterrand ,69269 Lyon

Architect
Tandem Agence
3 rue Rotrou, 28 100, Dreux
contact@tandemarchitectes.com
Tel.02 37 43 80 15

Energy Consultant
Axiome
Tel.03.27.96.78.84

Structural Engineer
SORAETEC BE structure
2 Rue de la Viscose, 38130 Échirolles

Tools used

Was the renovation process done following a specific methodology? No

RETROFIT SOLUTIONS

External Walls

Stone wall

Stone walls of 60 cm were insulated from the inside with 20 cm of mineral wool.

REPERAGE FACADE 2_rotated.pdf

U-value (post-intervention) [W/m2K]: 0,0 W/m²K

More Details

Original wall build-up

Stone :
600 mm

:
0 mm

Retrofitted wall build-up

Other - coated:
13mm

Stone :
600 mm

Insulation :
200 mm

Plaster :
12 mm

Painting (frescoes) :

Windows

Aluminum window, double glazing, presence of adjustable sun shades

The windows have been changed, now the windows are aluminum, double glazed, with the presence of adjustable sun shades.

The windows have been changed, the architect's wish was to preserve the image of the industrial hall building with a discreet intervention: creation of spandrels, resumption of existing forms. Technically, the joinery is in lacquered aluminum with thermal break, double glazing and installed in the continuity of the lining. For summer comfort, adjustable sun screens have been installed on the frames of the west and east facades, with solar control glazing in addition.

BSO AL80 B RAL 7016.pdf

New window U-value Frame [W/m2K]: 0,0

More Details

Existing window type	Aluminum frame
Existing glazing type

New window type	French opening window and drop down
New glazing type	Double
New shading type	adjustable sun shades

Other interventions

ROOF

GROUND FLOOR

MEASURES TO INCREASE AIRTIGHTNESS

ROOF

The light steel roof has been preserved, however 40 cm of cellulose wadding has been added in place of the 10 cm of rock wool.

The roof structure has been preserved, it is an important heritage element of this building.

More Details

Original roof build-up

Metal sheets - Lightweight sandwich panel roof:
160 mm

Other - rockwool :
100 mm

Retrofitted roof build-up

Metal sheets - Lightweight sandwich panel roof:
160 mm

Other - mineral wool:
400 mm

GROUND FLOOR

The existing ground was in beaten earth, realization of a paving, a heating floor as well as a waxed concrete.

Rammed earth has been replaced by simple paving, which recalls the original ground.

U-value (post-intervention) [W/m2K] 6,3

More Details

Original groundfloor build-up

Other - Rammed earth:
0 mm

Retrofitted groundfloor build-up

Other - waxed concrete:
0 mm

Other - heating floor:
0 mm

Concrete slab :
0 mm

MEASURES TO INCREASE AIRTIGHTNESS

The overall airtightness level of the building after renovation is very efficient and below the desired objectives. Etude thermique : n50≤0,9 vol/h - Q4Pa-surf≤0,6m3/h.m² Perméabilité testée : n50≤0,69 vol/h - Q4Pa-surf≤0,36m3/h.m²

HVAC

HEATING

VENTILATION

DOMESTIC HOT WATER

HEATING

Replacement of the oil boiler dating from 1982 with a 40 kW wood boiler located outside the heated volume. Installation of 2 wood pellet boilers - Boiler room in the basement outside the heated volume Emission by low temperature radiators in all rooms in place of old radiators and supply air. Heated floor on the ground floor - low temperature radiators in offices.

More Details

	New primary heating system	New secondary heating system
New system type	Boiler	Boiler
Fuel
Distribuition system	Radiating wall	Radiating floor
Nominal power	40 kW	kW

VENTILATION

Installation of two double-flow mechanical ventilation systems with an exchanger efficiency of 81% in the offices and the restaurant. Installation of an adiabatic system to reinforce the intervention of occupants on natural ventilation. The principle is to evaporate softened water in the ventilation duct. This system has the advantage of low energy consumption, ease of implementation, and no noise and refrigerant nuisance.

More Details

Original roof build-up	New ventilation system
Type ventilation system	Centralized
Type flow regime
Heat recovery
Humitidy recovery
Nominal power	kW
Electric power	kW
Control system

DOMESTIC HOT WATER

DHW production by the wood boiler - Presence of a 500 liter tank

More Details

	New DHW system
Type	wood boiler
Hot_water_tank	Yes
With heat recovery

RENEWABLE ENERGY SYSTEMS

Biomass

Wood boiler room

More Details

	Biomass System
Type
Storage size
Origin of biomass
Overall yearly production	kWh

Energy Efficiency

Energy Performance

Energy performance certificate: BBC-Effienergie renovation The project won the DEFFIBAT program with low energy consumption in Rhône-Alpes in 2017.

Energy Use

Heating
Primary Energy 88,6 kWh/m2.y
Consumption_estimation_Before: 374,2 kWh/m2.y
Consumption_estimation_After: 88,6 kWh/m2.y

Primary Energy
Consumption_estimation_Including_DHW: Yes
Consumption_estimation_Before: 374,2 kWh/m2.y
Consumption_estimation_After: 88,6 kWh/m2.y

Internal Climate

Acoustic Comfort

Attention has been paid to the acoustics of spaces with work on ceilings, floors and the installation of acoustic baffles.

Costs

Financial Aspects

Total cost of works excluding VRD € 1,240,000 excluding VAT, i.e. € 1,020 excluding VAT / m² of SHON RT. Public works grants € 97,280 Public aid comes from the Deffibat program by the Rhône-Alpes Region. The amounts of the work for the envelope (roof, walls and carpentry) amounted to € 370,000. The amounts of work for the systems (VMC, Chaudière, etc.) amounted to € 280,000.

Investment Costs

Total investment costs
1 240 000 € (total)

Environment

Water Management

building in the city center - pre-existing networks preserved

Transport and Mobility

building in the city center accessible by public transport. Lockers for recharging electric bicycle batteries available at the entrance