Abstract: The construction industry is one of the major sources of employment accounting for 7-8.5% of total employment across the world. The industry also has a 9% GDP share. Yet, it is one of the least innovative industries with housing prices soaring over the roof. A combination of pre-fab and modular construction design offers the potential to innovate the construction industry.
The UN-Habitat website claims that 3 billion people (40% of the world population) will need access to adequate housing by 2030 i.e. demand for 96000 new affordable and accessible housing units every day. The answer may not come from current methods of construction.
Conventional ways of constructing houses haven’t changed a lot in over a century. They are slow, unpredictable and expensive. There have been glimpses of hope surrounding technologies such as prefab and 3D printing to change the narrative. But before we dive into the technologies and understand how they are evolving, a short detour in construction history could be handy.
History of Construction:
In early human history, particularly during the stone age, construction was only used for creating shelter from harsh environmental conditions. These shelters were built to last for only a couple of days owing to the nomadic lifestyle. With the transition to a sedentary lifestyle since the birth of agriculture, permanent structures became prominent for both shelter and various other functions, such as food storage and religious ceremonies.
Early building materials such as leaves and animal hides were perishable. Humans slowly shifted to natural materials that were durable such as clay and timber, and eventually to synthetic materials such as bricks, steel and concrete.
Construction in its modern form began only in Ancient Egypt and Mesopotamia around 2500 BC. The structures such as the pyramids built by the Egyptians required a great deal of skill in design, engineering and architecture. They are also credited with using some form of cement in making concrete. The Romans and Greeks then tinkered with different formulations to build the great architectures of their era.
The Renaissance Era (14 to 16 Century AD) was a key period when Greek and Roman architecture elements were revitalized. Urban planning and the introduction of columns, pillars and domes in architectural designs became prominent.
The construction industry was truly revolutionized towards the late 19th Century. The pre-WWI era since the 1870s that witnessed the technological revolution saw ripple effects in the manufacturing process. Thanks to the Bessemer Process, mass production of steel ushered in construction projects that created bridges, railroads and skyscrapers.
Bessemer Process Credit: Sciencephoto.com
Steel is a non-combustible, recyclable, cheap material that is impervious to termites and is used in the construction industry even today. Thanks to the versatility and affordability of steel, the construction industry achieved a new level of productivity in the 20th century.
Credtis: Business Insider Australia
But innovation in the construction industry seemed to have stopped towards the late 1970s and the housing prices started to soar. Lack of innovation not only leads to stasis but also an increase in costs. Stagnancy in home building has not kept up with demand and population growth. Keeping the technology constant with no innovation leads to rising costs due to factors such as increasing demand, the addition of new features, the requirement of new safety measures or regulatory needs. Therefore, innovation needs to continue to meta-maintain the costs if not make it cheaper.
Homes are still constructed piece-by-piece with nails, bolts and hammers, on one hand, bricks and mortars on the other. Multiple aspects of the construction work are inefficiently distributed across multiple skilled trades(wo)men such as architects, plumbers, electricians, etc. Traditional construction methods are slow, fragmented, wasteful, and have poor thermal properties leading to an increase in energy use, increase in operating costs, and decrease in comfort.
All of that need to be innovated if we are to overcome the housing crisis.
There are 3 major innovations that are reshaping the construction industry.
- 3D Printing
Sometimes also known as additive manufacturing, 3D printing is an automated process that produces complex shape geometries. The blueprint is from a 3D CAD(computer-aided design) model.
How does 3D printing work?
Illustration of 3D printing a house. Credits: Architi
A typical 3D printer is similar to an inkjet printer operated from a computer. It prints a 3D model layer by layer. It builds up a 3D model one layer at a time, from the bottom upward, by repeatedly printing over the same area. Completely run on automation, a 3D printer creates a model over a period of hours by turning a 3D CAD drawing into sets of 2D, cross-sectional layers. Unlike an inkjet printer that uses ink, a 3D printer deposits layers of molten plastic. These layers are then fused using adhesives or UV light.
The idea of 3D printing originally came about in the 1980s to automate the manufacturing process which would reduce the manufacturing time from weeks to hours or days. 3D printing was touted to revolutionize the construction industry with the potential to save laborious work, reduce material waste as well as construction time, takeover risky operations performed by humans, etc. But 3D printing has been slow to have a real impact in the construction industry. One reason is that parts of the building are 3D printing offsite in a factory and transported to the site which turns out to be inefficient and costly.
There are two approaches taken by startups to tackle this:
- 3D print the entire building on-site
- 3D print modular components off-site that are easy to transport and assemble on-site
While 3D printing modular components will fasten the assembly process on-site, 3D printing the whole building is inefficient and hardly impacts the time and cost of home-building.
2. Prefab and Modular design
Among the big consumer products, gadgets(Apple) and cars(Tesla) got re-shaped. The next big product on the cards should be houses. Gadgets, clothes, cars etc are made in factories. As a result, they can be made low cost, high quality and abundantly available. The same should also apply to houses where a house is pre-fabricated as modular components in a factory using 3D printers as well as automated CNC(computer numerical control) machines and assembled on-site.
Credits: Cover Technologies Inc
Prefabricating modular components of buildings have been around for ages. Eg: Windows, doors, boilers etc. There have been a bunch of pre-fab houses over the last decade that have either failed to kick off or filed for bankruptcy. Most pre-fab solutions offer fixed designs and are not modular, and are therefore still expensive and complex. The key to accelerating prefab could lie in startups such as Cover that leverage modular design where roofs, walls and floors are prefabricated as panels that can be assembled together on site.
3. Alternatives to concrete
A major component of the construction work involves concrete and cement is an important ingredient in concrete. Producing cement involves converting limestone(CaCO3) to lime(CaO) which releases carbon dioxide as a byproduct. Our World in data attributes 3% of GHG emissions to cement and this doesn’t include the emissions released from energy inputs used to create cement. A 2020 report from Princeton University claims the concrete industry is responsible for 8% of overall global emissions when energy is added to the equation.
Concrete also generates a lot of waste and sometimes overloads the foundations. 3D printing can solve both the problem as the concrete printer has the ability to place concrete only where it is needed. While this approach is definitely more sustainable than traditional construction, the use of concrete is still carbon-intensive. A bunch of startups are tackling the challenge head-on by creating alternate concrete material that is sustainable.
A plethora of startups has emerged over the last decade focused on prefab such as nHouse(UK), Plant Prefab(US), PopUp House(France), Module(US), Blokable(US), Connect Homes(US), CubeHaus(UK) etc. While prefab companies are certainly eating into the housing market share, they are designed the conventional way and they still need to source architects, clients, electricians and other contractors which are big factors in the high cost of home building.
The company is taking a Tesla approach to modernizing houses. By starting with Accessory Dwelling Units(ADUs) as backyard guest houses for high-end customers - just like Tesla Roadster -the company aims to trickle down to making affordable and technologically advanced houses for everyone aka Model 3.
Cover designs modular components of walls and roofs that can be flat packed as panels and assembled on site. These panels are pre-painted, pre-engineered, pre-plumbed and pre-wired so that they can be quickly assembled on-site like legos. This drastically reduces time and costs. With 11.6 M $ in funding from some of the most forward-thinking VC funds such as Fifty years, Founders Fund, General Catalyst and Khosla Ventures and boasting alumni of Tesla, SpaceX, Apple and Amazon as employees, Cover is a startup with big bets poised to transform the construction industry.
Mighty Buildings is another US startup leveraging Prefab, 3D printing, 3D scanning and robotic technologies to radically innovate the construction of houses. The company claims it can produce its units in 2 or 3 weeks while cutting down costs by 40 per cent with almost zero construction waste as compared to a similar-quality construction by conventional methods.
The 3D printer used by Mighty Buildings, to build walls, prints layers of a thermoset composite which is lightweight, self-supporting, insulating and similar in strength to concrete while it consumes less time and is less expensive. Once the 3D scanner verifies the structure with the original digital design, the final detailing and texturing of the walls are executed by robotic arms to provide the finished product.
With 75M $ in funding, Mighty Buildings has also taken the high-end market by building ADUs before building affordable homes at scale.
While Mighty Buildings prefabricates the entire building in a factory and installs on-site, ICON primarily does onsite construction. ICON’s proprietary Vulcan 3D printer is designed to produce single-storey buildings with maximal design freedom at low cost and rapid time.
They also have their proprietary synthetic concrete called Lavacrete which they claim could be printed faster while outperforming the structure and durability of traditional concrete. This enables faster building time at a low cost. With 59M $ in funding, ICON is starting out with ADUs.
The startup also has plans to be the pioneer in building constructions off-world on Moon or Mars under Project Olympus. They have signed a contract with NASA to develop a 3D printed off-world construction system for the Moon.
Another startup that just entered the 3D printing construction foray is Terran Robotics. The core insight behind their solution is that most materials used in construction - clay, sand, straw etc. - are not amenable to 3D printing techniques and are very carbon-intensive as well as highly polluting. Terran Robotics are taking automation and robotics one step further in their construction process by training Unmanned Aerial Vehicles(UAVs)/Drones to emulate and improve upon traditional earthen building techniques.
They are trying to address energy inefficiency both when a building is being occupied, as well as the energy and pollution involved in actually creating the building using reinforcement learning to train the drones in the construction process. The company is currently raising their first round of funding.
Credits: Factory OS
Factory OS vertically integrates solutions for cost-saving efficiencies across the construction value chain. They integrate innovation, architecture, tradespeople, engineering, design in factory and assembly as well as installation on-site. By building an end-to-end supply chain system and relegating most work off-site, Factory OS’ controlled environments support year-round 12 hours a day off-site construction.
Factory OS leverages BIM(Building Information Modelling) digital prototyping, precision manufacturing, robotics and smart home security and temperature control services.
By concurrently working both in the factory and on-site, the startup drastically reduces construction time. Backed by Alphabet, Autodesk and Facebook, the company has raised 77.7M $ in funding so far. The company claims to produce 40% less waste owing to precision cutting and industrial storage, in addition to reduced carbon footprint due to fewer transportation requirements.
While the above-mentioned companies and technologies are surely exciting, the biggest bottleneck may yet be the construction regulatory environment. This is why companies like Cover are closely working with regulators to jointly innovate the construction space.