Who are we?
Demetair is a Toulouse-based company founded on the belief that urban greening is one of the most effective ways to tackle the climate challenges facing cities:
reduces heat islands
collects rainwater
stores CO₂
supports biodiversity
and improves the thermal insulation of buildings.
The benefits are well proven.
The problem has always been elsewhere: traditional substrates are too heavy, too complicated to install and too expensive to maintain.
That is exactly the problem that VGHolz solves.
The benefits are well proven.
The problem has always been elsewhere: traditional substrates are too heavy, too complicated to install and too expensive to maintain.
That is exactly the problem that VGHolz solves.
A substrate designed
to remove all obstacles.
Ultra-Light
40 kg/m³ when dry — up to 20 times lighter than a traditional substrate.
Makes green roofs possible on renovation projects.
Organic
98% organic matter, made from local plant fibers.
A sustainable, peat-free solution that supports biodiversity.
Made in France
Designed and assembled in France using local resources.
A controlled, durable, low-impact solution.
Quick installation
Easy to handle and install
Fits in with the building’s existing structure without the need for major building work.
Ultra-Light
40 kg/m³ à sec — jusqu’à 2× plus léger qu’un substrat classique
Makes green roofs possible on renovation projects.
Organic
98% organic matter, made from local plant fibers.
Favorise la biodiversité et s’inscrit dans une démarche durable.
Made in France
Designed and assembled in France using local resources.
A controlled, durable, low-impact solution.
Auto-portant
Sans fixation structurelle
S’adapte aux toitures existantes sans travaux lourds.
A Solution Designed for Everyone Who Builds, Manages, and Develops Urban Buildings
Property Owners and Social Housing Providers
More valuable, compliant, and attractive building assets.
Industrial Companies and Businesses
High-performance roofs that support your CSR strategy.
Municipalities and Local Authorities
Cooler, more permeable, and more livable cities.
Architects and Specifiers
A complete technical solution with a single point of contact.
Awards and Recognition
Solar Impulse Label
Certified as an “Efficient Solution” for our contribution to environmental challenges.
Coq Vert Community Member
Member of the Coq Vert community, the french network of companies committed to ecological transition.
Top 50 Proptech Europe
Selected among the 50 most promising proptech companies in Europe by the PropTech Breakthrough Awards.
Holcim Accelerator Winner
Chosen among the most promising startups in sustainable construction.
CLEANTECH OPEN FRANCE
Finalist in France’s leading cleantech innovation competition.
News RSE 2025 Award Winner
Recognized for our commitments to corporate social responsibility.
Jardins Jardins 2025 Winner
Recipient of two awards: Grand Prix Valhor du Petit PotagerGrand Prix de la Création Paysagère
Erasmus+ European Project
Winner and coordinator of the Urban Gardens for Communities project, an innovative EU-funded program combining ecology, inclusion, and digital technology.
Awards and Recognition
Solar Impulse Label
Certified as an “Efficient Solution” for our contribution to environmental challenges.
Coq Vert Community Member
Member of the Coq Vert community, the french network of companies committed to ecological transition.
Top 50 Proptech Europe
Selected among the 50 most promising proptech companies in Europe by the PropTech Breakthrough Awards.
Holcim Accelerator Winner
Chosen among the most promising startups in sustainable construction.
CLEANTECH OPEN FRANCE
Finalist in France’s leading cleantech innovation competition.
News RSE 2025 Award Winner
Recognized for our commitments to corporate social responsibility.
Jardins Jardins 2025 Winner
Recipient of two awards: Grand Prix Valhor du Petit PotagerGrand Prix de la Création Paysagère
Erasmus+ European Project
Lauréat et coordinateur de l’appel à projet Urban Gardens for Communities, un programme innovant financé par l'UE, mêlant écologie, inclusion et numérique.
Want to Learn More About Demetair?
Our CEO, Hélène Mariette, shares our vision, technology, and impact in an episode of The Impacters podcast.
50 minutes to understand everything.
Want to Learn More About Demetair?
Notre CEO, Hélène Mariette, répond à tout dans cet épisode de The Impacters : notre vision, notre technologie, notre impact. 50 minutes pour tout comprendre.
Trusted Partners
Your Roof May Be Suitable for Greening
Free feasibility assessment. Response within 48 hours.