Climate change:
6 startups revolutionizing construction

With the acceleration of the climate challenge, the construction sector, eminently aware of its environmental footprint, is strengthening its capacity for innovation in order to imagine solutions and processes that reduce the sector's carbon footprint. A look at 6 start-ups that are revolutionizing construction.

Construction’s newest, most sustainable companies

The rapid rise of cutting-edge technologies in the construction industry has led to its own portmanteau – ConTech. It comprises an array of innovations designed to make industry processes faster, more efficient, and safer. But possibly the biggest benefit from this rapidly growing area is its environmental one, helping the industry significantly reduce its impact on our environment.

As the effects of the climate crisis are felt in all corners of the world, the construction sector must play its part today – rethinking its methods, materials, and approaches. Here are six revolutionary solutions that are helping construction become even more sustainable. Six solutions driven by six start-ups and supported by NOVA by Saint-Gobain:


I. Planning a carbon neutral building: CAALA

Standing for Computer Aided Architectural Life-Cycle Assessment, this Germany-based start-up offers modelling and design software that can help building designers realize carbon-neutral buildings and decarbonize existing ones. Aimed at project developers, architects, and advisers, CAALA’s analytics software helps them optimize the sustainability of their building projects at every stage, from planning to design to construction and operation.

Developing more energy-efficient buildings is a win-win – good for both the inhabitants and the planet. And it starts at the decision stage. Whether it is for a new build or a renovation, understanding the impact of every construction decision makes low carbon buildings a cheaper and more realistic option.

Why is it revolutionary?

CAALA utilizes Life-Cycle Assessment (LCA) and Life-Cycle Costing (LCC) analysis software to identify the best ways to optimize and decarbonize building projects.  Creating a virtual 3D twin of the proposed building or renovation, parameters around materials, construction technology, CO2 intensity, and costs can then be added. The software then analyses and visualizes the results, providing an estimate of the CO2 emissions, energy demand and costs during both the construction and operation stages. The architects and developers can then adjust the parameters to find the best outcome for their final designs.

To read : Real buildings, virtual twins: constructing the future

II. Concrete without cement and sequestering carbon dioxide carbon: CarbiCrete

Headquartered in Canada, CarbiCrete has patented a technology that produces concrete without cement and sequestering carbon dioxide carbon from industrial by-products and carbon dioxide. The process uses slag, an industrial by-product from steel factories, to replace cement as a binding ingredient in precast concrete products.

Ubiquitous with the built urban environment, concrete is the most widely used man-made material. It also has a massive carbon footprint, primarily due to its main ingredient. Every tonne of Ordinary Portland Cement, an essential ingredient of concrete, emits 622kg of CO2. Added up, cement production contributes to 8% of the global total of CO2 generated 2.5 billions tonnes every year. Furthermore, making cement is very energy intensive using long rotating kilns which are heated to 1500°C.


Why is it revolutionary?

The innovative aspect of CarbiCrete’s technology is not only does its process replace cement with an industrial by-product, but it also sequesters carbon in the final product. Once the concrete mix of steel slag and other materials is poured into conventional block-making machines, it needs to be cured. CarbiCrete has patented a curing process of injecting CO2 into the fresh concrete to provide strength, while permanently sequestering CO2 within the resulting products. CarbiCrete’s concrete blocks have up to 30% more compressive strength, are more resistant to freezing and thawing and have the same level of water absorption than typical concrete.

The adoption of CarbiCrete’s technology at a typical plant producing concrete masonry units (CMUs) has a profound environmental impact on an annual basis: Approximately 20,000 tonnes of CO2/equivalent are abated and removed, around 4,400 cubic meters of water saved, and 33,000 tons in landfill avoidance.

To read: Low-carbon building: Five R&D projects to watch 

III. Reusable walls: JUUNOO

Belgian startup JUUNOO is revolutionizing wall construction to reduce installation time and allow materials to be reused. The company produces easy-to-install, reusable office walls that can be used to make partition walls, meeting boxes, phone booths, and glass doors. At the end of its life, the wall doesn’t have to be demolished but instead can be dismantled and reused. It can be installed seven times faster than a traditional wall and can be positioned and repositioned over and over again.

Reduce, reuse, recycle is the mantra for living more sustainably and it can be equally applied to buildings. Every year partition walls worth $320 billion are demolished and disposed of with 99% of the world’s walls ending up in landfill. They are responsible for 1% of all CO2 emissions worldwide. That is the same as the amount of emissions produced by all air and shipping traffic combined.

Why is it revolutionary?

Using circular products that are designed to be dismantled, recovered, and reused, not demolished and discarded, helps to make office buildings far more sustainable. JUUNOO walls are designed to be a one-time purchase. They can be reused time and time again and the company will even buy back partition walls from customers if they are no longer needed.

To read: Reversible building, modular building: what's the difference?


IV. Bamboo ­– the new aluminium: African Bamboo

The mission of African Bamboo, a natural fiber company, is to create sustainable alternatives to conventional building materials like plastics, aluminium, steel, glass, and concrete.

The construction industry consumes 40-50% of all primary raw materials ­– by far the most resource intensive industry. Embodied carbon, or the material that goes into a building’s construction like steel and cement contributes more than 3,000 mega tonnes of CO2 per year. These heavy construction materials are also expensive and resource-intensive to manufacture, transport and install into buildings.

Why is it revolutionary?

African Bamboo has designed its solid fiber-reinforced products to be lightweight (half as much as concrete), strong (3 times higher strength-to-density ratio than stainless steel), and durable (lifecycle of 20 years when subject to outdoor weathering). The company foresees its products having a wide variety of use cases including cladding, furniture, flooring, and structural walls.

The company also sources its bamboo in a socially, environmentally, and economically sustainable manner working with up to 2,200 farmers in 31 cooperatives in sites across Ethiopia, to cultivate the bamboo in a manual, low footprint way.

To read : From products to materials... is everything natural necessarily more sustainable?

V. Tailor-made prefabricated homes: Unity Homes

Unity Homes is a housebuilder from the northeast of the United States that uses technologically advanced prefabrication processes to create energy efficient, sustainable houses while minimizing waste.

Unity has developed five flexible, expandable platforms that serve as starting points and then based on information about the construction site and the preferences of the buyer. The company then assembles a 3D model of the home design using a range of predesigned elements, such as kitchens and bedrooms. The digital model drives computer-controlled equipment in a production facility, where the large components of the home are prefabricated. They are then transported to the construction site and assembled by a team of carpenters.

Why is it revolutionary?

Digital technology, such as the ones Unity use, are driving a resurgence in prebuilt modular homes. Not only are they more efficient and cost effective to build but

leave a much smaller environmental footprint that a conventionally built home. A modular home is built with prefabricated trusses and frames can reduce waste by 52% and produce up to 45% less carbon than traditionally built homes.

To read: Is prefab the revival of construction?

VI. 3D printed affordable housing: Tvasta

Tvasta is an Indian manufacturing materials start-up focuses on bringing efficiency to the construction industry through technology. The business develops concrete 3D printing technology that can be used to 3D print homes and has constructed India’s first 3D printed house in 21 days.

Tvasta’s focus is to make the process available to all sections of the construction industry, including affordable housing and large-scale infrastructure building. To that end, one project saw Tvasta collaborate with Saint-Gobain to construct two 3D printed doffing buildings, where healthcare workers could remove and dispose of personal protective equipment during the COVID-19 pandemic.

Why is it revolutionary?

The sustainability benefits of 3D construction methods stem from the ability to hugely reduce waste and only use the precise amount of materials required. It is also quicker and safer than conventional construction.

To read : Will printers build the homes of tomorrow?

Through innovative design and different new processes, the construction industry, despite its perception as a ravenous consumer of resources and emitter of carbon, can and is changing the course of the sector, moving it closer towards the global goal of carbon neutrality by 2050. The six start-ups mentioned cover all stages of the construction pipeline (prior to demolition). Powered by a desire to make a change, driven by greater consumer demand and support from bigger players in the construction industry, these start-ups are part of a sea change making construction kinder to the planet.


Crédit : Shutterstock/NDAB Creativity ; Shutterstock/Bannafarsai_Stock