Oktave is the regional energy‑renovation service for the Grand Est region of France, created by the Grand Est Regional Authority and ADEME (the French Agency for Ecological Transition). It was launched in 2015 to accelerate large‑scale home energy renovation and became a semi‑public company (SEM) in 2018, supported by major public and financial partners.
Oktave’s mission is to make high‑performance home renovation easier, safer, and more accessible by providing homeowners, landlords, condominiums, and real‑estate professionals with technical expertise, financial engineering, and full project support from initial assessment to final delivery.
The service acts as a one‑stop shop offering:
- personalized renovation scenarios,
- energy audits,
- contractor selection support,
- project management assistance,
- full financial guidance (including subsidies, Eco‑PTZ loans, and advance payment of grants).
Oktave operates across the entire Grand Est region through a network of renovation advisors placed close to communities, working alongside the national France Rénov’ public service.
1. Individual Homeowners
Oktave supports homeowners from the initial diagnostic phase all the way to final project handover, providing a tailored renovation plan, assistance with contractor selection, technical supervision of the works, and comprehensive financial engineering (aid identification, application management, and advance funding of subsidies).
2. Purchase + Renovation (Real Estate Agents)
Oktave makes it easier to sell energy‑inefficient homes by providing agents and their clients with a clear seller’s audit, a coherent preliminary cost estimate, an assessment of available incentives, and reliable tools that reassure buyers and remove barriers to completing the transaction.
3. Single‑Property Owners / Property Managers
For landlords, Oktave offers a complete preliminary project including an energy audit, subsidy simulations, consultation with qualified contractors, and administrative assistance, ensuring a secure and profitable renovation of rental properties.
4. Condominiums (Property Managers / Syndics)
Oktave assists building managers with a comprehensive methodology for steering energy‑renovation projects: technical‑financial optimization, implementation of collective loans, expert participation in General Assembly meetings, and support throughout all stages—from the audit to the vote on renovation works.
15 rue des francs-bourgeois
67000 Strasbourg
France
Recent Energy Renovation Projects in the Grand Est Region
Oktave is the regional energy‑renovation service for the Grand Est region.
Our mission: to secure, simplify, and manage high‑performance renovation projects for all types of housing — single‑family homes, rental properties, and condominiums.
Independent and backed by the Grand Est Regional Authority, we support both private individuals and professionals with comprehensive technical, methodological, and financial expertise.
🔧 What We Deliver Across the Grand Est Region
We work on a wide range of buildings:
- Single‑family homes from the 1930s to the 1980s, pavilions, townhouses, terraced houses, and period homes
- Condominiums of all sizes, from small 4–14 unit buildings to large residences with 100 to over 400 units
- Older or unique buildings such as former schools or heritage properties
Across the region, our projects consistently deliver:
✔ Major energy‑consumption reductions, often between –40% and –70%
✔ Significant energy‑rating improvements (e.g., from F to C, E to A, or E to B)
✔ Heating decarbonization (air‑to‑water heat pumps, geothermal systems, replacement of oil/gas boilers)
✔ Improved thermal comfort in both winter and summer
✔ Increased property value after renovation
🔍 End‑to‑End Support at Every Stage
For every project, Oktave provides a structured, full‑scope service including:
- A personalized audit and renovation plan, adapted to the building and the occupants' budget
- Consultation, selection, and coordination of qualified contractors
- Technical supervision of the renovation until final acceptance
- Tailored financial engineering, including identification of subsidies, preparation of applications, and advance funding to ease household cash flow
- Independent, solution‑oriented advice ensuring the final energy performance
🏡 Examples of Recent Projects
Our work spans a wide variety of renovations across the Grand Est region, including:
- Full renovation of a period home in Kaysersberg
- Transformation of a townhouse in Haguenau or a 1960s home in Brunstatt
- High‑performance upgrades to pavilions in Strasbourg, Metz, Commercy, Sundhoffen, Bar‑le‑Duc, and more
Major condominium renovations:
- Cité Européenne (97 units)
- Villa Krafft (geothermal heat pump)
- Place du Marché – Strasbourg
- Constellation Metz (117 units)
- Montigny‑les‑Metz (34 units, 61% energy savings)
- And many more projects from 14‑unit buildings to large 100+ unit residences across the region
🎯 Our Goal: High‑Performance, Durable, and Financially Accessible Renovations
Thanks to proven solutions, independent expertise, and tools tailored to both individuals and local communities, Oktave helps deliver long‑lasting improvements in:
- Energy performance
- Occupant comfort
- Property value
- Reduction of emissions and energy expenses