Case Study: L'Ophis at Saint-Genès-Champanelle: learning-by-doing (pilot) project for timber field

Short Description

20 homes designed by architect Alexis Magnier that will allow tenants to save 28% on their hot water and heating bills.

Timber frame homes labelized BBC (low consumption building) built by Ophis: an exemplary operation, filmed continuously (www.ophis.fr), which will train businesses to new more efficient construction processes.
This is going even further in the search for economies of charges for tenants and the development of new wood construction techniques.

Monitoring of dwellings energy consumption at St Genès-Champanelle and Pontgibaud.

The purpose of this monitoring is to compare the actual consumption of instrumented dwellings with theoretical results.

The conventional primary energy consumption for a building BBC is between 35 and 75 kWh / m² / year (70 kWh units planned for St. Genès-Champanelle). In comparison, a building subjected to the RT 2005 consumes between 120 and 220 kWh/m²/year. Accordingly, a building with similar characteristics, but subject to the RT 2005, should also be monitored in order to compare actual consumption by evaluating the differences in overall consumption and consumption by uses (heating, gas, electricity, cold water, hot water) and their costs of design and implementation.

Monitoring:

• CO2 content, temperature, hygrometry, wind speed and direction outside of the dwelling

• CO2 content, temperature, hygrometry inside the dwelling

• temperature setpoint programmed on the thermostat

• heating consumption,

• gaz consumption,

• consumption and temperature of cold water,

• consumption and temperature of hot water,

• extraction rate in the ventilation

• overall electricity consumption,

• Electricity consumption by uses (lighting, boiler supply, ventilation…)

Links between the different materials will be wired.

A central data acquisition will be placed in the building. She will be able to store and transmit data to the Ophis server. This one will be equipped with software for data processing.

The cost of instrumentation for 1 dwelling is between 3000 and 5000 € HT with about 18 sensors and meters including only the supply of equipment, wiring, calibration and commissioning on site.

For 12 dwellings equiped, the cost will vary from 36 000 to 60 000 € HT.

Application will be made in order to obtain a grant of 50% from ADEME.

Key Elements

Environmental Design

The timber frame is a manufacturing process that allows good air tightness, reduced by 4 months the construction time (precast panels are set up at the factory and assembled on site) and limit disturbance to local residents.

Wood is a renewable, recyclable, energy-efficient material. It allows insulation in avoiding thermal bridging, suppresses the effects of condensation (good quality of ambient air) and helps to fight against the greenhouse effect.

Thermal Insulation

1. Double wall insulation layer: 150 mm mineral wool between studs + 60 mm mineral wool wall to total thermal resistance of 6.10 m².

2. Floor insulation under screed

3. Roof insulation in double layer with 220 mm + 100 mm mineral wool

4. Window double glazing with reinforced thermal insulation

5. Controlled mechanical ventilation and humidity sensitive single-flow low-power ventilators

6. Individual condensing boiler

Funding

Budget: 1,7 M € TTC

Funding: Ophis (79%), France (54 500 €), Clermont Communauté (100 000 €), Conseil Régional (96 285 €), Conseil Général (69 225 €), Commune de Saint-Genès-Champanelle (39 600 €), Logehab (16 000 €).

This project is the recipient of the call for proposal Low Consumption Building launched by ADEME and the Auvergne region background Prebat.

Certification

ISO 9001 (2008)

Main Results

Lessons learned