Hemp shiv and lime, cast into walls that keep rooms quiet, hold a steady temperature and store carbon for the life of the building. Based in Kolkata, building across India.
Hand-cast hempcrete samples from our R&D work
Our Rajarhat project in Kolkata is the first documented hempcrete interior in the region.
Thermal data from Mahindra TERI Centre of Excellence. Acoustic data from IIT Kharagpur.
About 110 kg of CO₂ stays locked in every cubic metre of wall.
Hempcrete is a bio-composite of hemp shiv and a lime-based binder. It creates walls that breathe, insulate, and actively sequester carbon. It is one of the most advanced sustainable building materials available today.
The natural fibre matrix absorbs sound frequencies, dramatically reducing noise transmission between spaces.
High thermal mass stabilises interior temperature, reducing energy consumption and HVAC dependence year-round.
Hemp absorbs CO₂ as it grows and the wall keeps sequestering carbon once set: a wall that gives back to the planet.
Naturally hygroscopic, it regulates humidity and prevents mould without chemicals or synthetic barriers.
“A wall that doesn’t just divide space. It elevates it.”
These are measured, published figures, not marketing claims. Hempcrete’s performance advantage over conventional materials is quantifiable, peer-reviewed, and increasingly recognised by India’s own green building standards.
| Property | Value | Source |
|---|---|---|
| Thermal conductivity | 0.22 W/mK | Mahindra TERI Centre of Excellence, Gurugram. ISO 22007-2:2022, Report MTCoE-1202025001 |
| Heat capacity | 0.300 MJ/m³K | Mahindra TERI Centre of Excellence, Gurugram |
| Thermal diffusivity | 0.742 mm²/s | Mahindra TERI Centre of Excellence, Gurugram |
| Density | 625 kg/m³ | Mahindra TERI Centre of Excellence, December 2025 |
| Transmission loss, 50 mm panel | 15.2 dB at 500 Hz | IIT Kharagpur, Dept. of Mechanical Engineering. ASTM E2611 and E1050 |
| Sound absorption | NRC up to 0.80 | Reference value for hempcrete |
| U-value, 300 mm wall | ≈ 0.73 W/m²K | Estimate from tested conductivity |
| Carbon stored | ≈ 110 kg CO₂/m³ | Reference value for hempcrete |
| VOC emissions | Zero | Hemp shiv and natural lime only |
| Lifespan | 100+ years | Reference value for lime-bound hemp walls |
Lower means less heat passes through the wall. Tested hempcrete is about four times better than red clay brick and five to eight times better than standard concrete.
At 0.22 W/mK, hempcrete sits far ahead of the two most common wall materials in Indian construction. Within a timber frame it acts as a monolithic envelope, giving structural infill and thermal insulation in a single layer, with no separate insulation boards or cavity systems.
Glass wool and EPS reach conductivity as low as 0.03 W/mK, but their near-zero density means they carry almost no thermal mass. They stop heat transfer but cannot store it.
Hempcrete’s heat capacity of 0.300 MJ/m³K lets the wall absorb heat at peak temperatures and release it slowly as the space cools. Interiors stay measurably cooler in summer and warmer in winter, without extra mechanical load.
India’s national green building standard, GRIHA, awards points for alternative materials made from industrial or agricultural waste. Hempcrete is made from hemp shiv, a direct agricultural byproduct of hemp fibre processing, which gives developers and architects a documentable contribution towards certification.
A 300 mm hempcrete wall reaches a U-value of about 0.73 W/m²K. Systems such as AAC with mineral wool can reach 0.22 W/m²K on paper, but in humid climates raw thermal resistance is only part of the story.
Hempcrete regulates heat and moisture together, passively, with no added systems or treatments. That is why it delivers better real-world comfort than walls that manage only one of the two.
Independently verified, November to December 2025
Arete’s landmark project in Rajarhat, Kolkata marks the first proven application of hempcrete for interior acoustic insulation in Eastern India. The challenge: a premium residential space requiring measurable sound attenuation without compromising design integrity.
Our solution deployed hempcrete panels across key partition walls and feature surfaces, achieving significant sound dampening while delivering a texturally rich, naturally finished aesthetic that no synthetic material can replicate.
“The hempcrete walls have transformed the space entirely. The sound quality is exceptional and the natural texture gives the room a character I hadn’t imagined possible. Arete delivered something truly beyond expectations.”
Client, Rajarhat residence, Kolkata, 2025
End-to-end hempcrete interior solutions, from material consultation through to final installation, for residential, commercial and hospitality projects.
Hempcrete panel installation for measurable sound dampening. Ideal for home theatres, studios, luxury residences and corporate meeting rooms seeking acoustic precision with natural aesthetics.
Hempcrete wall systems engineered for thermal mass performance, keeping spaces cooler in Kolkata’s heat and reducing HVAC reliance. A luxury upgrade with measurable energy savings.
Hempcrete’s natural texture creates distinctive, tactile feature walls that serve as architectural statements. Natural pigments can be layered into the cast, so no two walls are alike.
Advisory services for architects, interior designers and developers seeking to integrate hempcrete. We provide specification, sourcing guidance and technical support throughout the design process.
Bespoke hempcrete applications for unique spatial challenges. From curved walls to complex acoustic environments, our team pushes the boundaries of what bio-based materials can achieve in Indian interiors.
Design and development
16 years spent shaping interiors and sustainable habitats have given her an instinct for materials that don’t merely fill space, but elevate it. She is the quiet force behind Arete’s design philosophy, translating ecological intelligence into forms that feel effortless, necessary and deeply human.
Design innovator
With 12 years at the intersection of design and R&D, he transforms raw ideas into systems of beauty and performance. His work does not chase trends but anticipates them, merging spatial clarity with scientific nuance.
Strategy
A rare duality: the analytical discipline of a Chartered Accountant and the vision of someone who understands what sustainable enterprises must become. His expertise in financial architecture ensures that Arete grows with intention: ethical, stable and strategically sound.
Marketing and business development
Raj combines the financial discipline of a former banker with the market instinct of a seasoned real estate leader. With 20 years of experience in luxury real estate, buyer behaviour and market cycles, he leads Arete’s marketing strategy and business development.
Every wall is a choice. Hempcrete actively sequesters carbon, supports healthy indoor air and contributes to net-zero building targets, while delivering premium acoustic and thermal performance.
Hemp absorbs CO₂ as it grows and locks it into the wall once set in lime. Every square metre of hempcrete installed reduces a building’s carbon footprint, contributing directly to net-zero and carbon-negative construction targets.
Synthetic insulation, gypsum boards and adhesives off-gas VOCs that compromise indoor air for years. Hempcrete contains no synthetic chemicals, no formaldehyde and no petroleum derivatives, making it one of the healthiest wall materials available for Indian homes.
Hemp is ready for harvest in 90 to 120 days, needs no pesticides and regenerates soil health. Hempcrete is a truly circular material: grown from the earth and returned to it.
India’s path to net-zero construction begins at the wall.
As India moves toward its 2070 net-zero commitment, the materials used in construction will decide whether that target is reachable. Hempcrete is not a future solution. It is a deployable, tested and commercially viable path to lower-carbon, healthier buildings today.
Thoughts on sustainable interiors, hempcrete innovation and the future of conscious design in India.
Most building materials add carbon to the sky. Hemp does the opposite, pulling it down as it grows and keeping it locked in the wall. The story, from field to finished room.
Read the articleArete Sustainable Synergies, Arete Journal
The summers keep breaking records, the monsoon keeps arriving late, and the air keeps getting stickier. A look at how we’re thinking about homes that can take it.
Read the articleArete Sustainable Synergies, Arete Journal
AAC blocks are fine. But once you look at how a wall behaves through a Kolkata summer, and what it cost to make, hemp and lime win on most counts. Our take on the comparison.
Read the articleArete Sustainable Synergies, Arete Journal
Can’t find what you need? Email contact@aretesynergies.com and we’ll answer within a working day.
Hempcrete is a bio-composite made from hemp shiv and natural lime. In Indian interiors, it is specified as wall infill panels for acoustic insulation, thermal regulation, and decorative feature walls. It is carbon-negative, 100% VOC-free, and independently tested by IIT Kharagpur and Mahindra TERI Centre of Excellence.
Hempcrete achieves a thermal conductivity of 0.22 W/mK, 4× better than red clay brick and 5–8× better than standard concrete. It also sequesters ~110 kg of CO₂ per m³, produces zero VOC emissions, and delivers superior acoustic performance, making it one of the most advanced wall materials available in India today.
Yes. Arete Sustainable Synergies is based in Kolkata and serves residential, commercial, and hospitality projects across India including Mumbai, Delhi, Bangalore, Hyderabad, and Chennai. Contact us at contact@aretesynergies.com to discuss your project requirements.
Yes. Hempcrete is made from hemp shives, an agricultural byproduct, making it eligible for GRIHA points under the alternative materials criteria. It also contributes to thermal performance and indoor air quality credits, giving developers a measurable green building advantage.
Absolutely. Hempcrete’s hygrothermal properties, its ability to regulate both heat and moisture simultaneously, make it particularly well-suited to India’s climate. Unlike synthetic insulation that only manages heat transfer, hempcrete buffers temperature swings and absorbs excess humidity, delivering real-world comfort that outperforms conventional systems in tropical conditions.
Yes. Hempcrete is carbon-negative. It sequesters approximately 110 kg of CO₂ per cubic metre, meaning the wall itself offsets carbon rather than adding to it. Combined with its thermal efficiency (reducing HVAC energy consumption) and 100% bio-based composition, hempcrete is one of the most powerful tools available for net-zero and low-carbon construction in India.
Hempcrete contains no synthetic binders, formaldehyde, or petrochemical derivatives, emitting zero VOCs from day one. Its hygroscopic nature naturally regulates indoor humidity, inhibiting mould and bacteria growth without chemical treatments. For families, children, and health-conscious homeowners, hempcrete is among the cleanest and healthiest wall materials available in India.
Hemp grows in 90–120 days without pesticides, regenerates soil health, and absorbs more CO₂ per hectare than most crops or trees. Once harvested, the woody core (hemp shiv) is mixed with natural lime to produce hempcrete, a wall material that is 100% bio-based, biodegradable, carbon-sequestering, and durable for over 100 years. It is one of the most genuinely circular building materials in the world.
We work with architects, developers and homeowners who believe great design and ecological responsibility belong together.
Whether you’re scoping a new project, curious about hempcrete specifications or looking for a material partner, we’d love to hear from you.